Weapons and Synergies

Builds and synergies

Builds The 7 active and passive abilities you'll be able to use
Synergy How well the actives and smaller extent passives work together.
Rotation The order in which you will spend most of the time pressing your number keys.

This is where it gets nitty gritty and you spend hours (or at least minutes) agonizing over what to choose.

What you need to pay most attention to:

1. do your passive match your actives as stated before, some passives are highly specific to weapon, attack type, or active ability.
2. will your rotation be too complicated more about this below, but will you be able to use your consumers after 2, 3, or 5 builder hits? Does the damage of your consumer depend on the number of resources built?
3. what are you building towards? keep in mind your end goal here. Are you tanking, leeching, healing, dps, buffing, or pvping?
4. what can you currently use at the moment Some people may link builds that you can not use yet. You can work towards it or maximize what you can do with the weapons you've already chosen or can use.

Overviews of Roles:
         1. Soloing - Your standard build for going around the various zones interacting with PvE content. Typically you want to do a mix of dps and damage mitigation (Blocking, evading, healing, impairing, hindering, etc.)
         2. Tanking - This ain't like other MMOs. You do not just stack HP and expect to be able to tank. You are in charge of building massive amounts of hate so no matter how much damage your team mates do, your damage and hate will still outweigh theirs. Agitator in the Misc Abilities is your main passive for that and look at your builders to see which ones say "Generates large amounts of hate". You are also in charge of impairs and making sure any mobs/adds that spawn attack you instead of your group members.
         3. Healing/Leeching - You are in charge of making sure your group members don't die. DO NOT PRE HEAL. That's the best advice I can give you if you want to live. Healing generates a lot of hate and you'll normally be second in line on the hate chart. First is the tank. Make sure you have plenty of utilities that can give big heals or buff your healing for the "Oh crap they're dying!" moments.
         4. Buffing - You're in charge of DPS and using your buffs at the right time. Standard buff builds are either DABS, SF, and then your situational buffs of CU or WW. Please see my other guides for the meaning of the acronyms.
         5. DPS - Give it everything you've got but for the love of your group Do not shoot before the tank gets in there. Do not impair. Do not hinder. and just watch the AoE on that the bosses or trash spawn and you're good.

Below are some weapon combinations that are useful and most widely seen. This list is by no means exhaustive.

Tanking

Main thing you want to pay attention for in these builds. What builders generate hate, what impairs do you have, and add control as well.

Blade/Hammer -
Blade Torrent is really your only builder as you need to start building hate right away and Grand slam requires weakened to be on the mob already to make you gain hate.
Crimson Theater or Raging Volcano is great to use on top of your consumers.
Trial by Swords, Stunning Swirl, Art of War, Beatdown, Shockwave, Eruption are your impairs.
Saving grace is a good utility but situational at best.

Chaos/Hammer -
Escalation is really your only builder as you need to start building hate right away and Grand slam requires weakened to be on the mob already to make you gain hate.
Discord rising or Raging Volcano is great to use on top of your consumers.
Chaotic Pull, Domino Effect, Beatdown, Shockwave, Eruption are your impairs.   

Chaos/Blade -
Blade Torrent or Escalation should be used as builders.
Crimson Theater or Discord rising is great to use on top of your consumers.
Trial by Swords, Stunning Swirl, Art of War, Chaotic Pull, and Domino Effect are your impairs.
Saving grace is a good utility but situational at best.

Healing

Main thing you want to pay attention for in these builds. What generates Heals, Heals over Time, and Shields.

Fist/Pistol (Also known as Fistol)
Nuture and Cauterize are both good builders.
Surgical steel is a good consumer.
Fired up, Greater Good, Back up Drone, Win-Win are all good utilities.

Fist/Blood
Nuture, Cauterize, Ruby Curtain are all good builders.
Surgical steel and The Scarlet Arts are a good consumers.
Fired up, Cold Blooded, Transfuse and Abuse, are all good utilities.

Leeching

Leeching is having to balance DPS power with Healing power, the more DPS you do, the more healing you do, but you also need +Healing to get the maximum effect. The standard Leech build is Assault Rifle/Blood but there's other permutations out there.

Assault Rifle/Blood -
Anima shot is best bet for your builder. You can replace it with Anima Burst later.
Anima Vessel, Transfuse Anima, and Scarlet arts are good consumers.
Cold Blooded, Transfuse and Abuse, Energize, and Reap and Sew are all good utilities.

Assault Rifle/Hammer
Anima shot is best bet for your builder. You can replace it with Anima Burst later.
Anima Vessel, Transfuse Anima, and Molten Steel are good consumers.
Full Momentum, Lock and Load, Do or die, Energize, or Reap and Sew are all good utilities.

Buffing

Buff builds are just DPS with added utilities to give the party bursts of DPS at certain points in a fight.
Do not sacrifice your DPS capabilities for having more buffs.

Pistol/Shotgun -
The Business or Powder Burn are good builders. Eventually replace either The Business with Hair Trigger or Powder burn with Striker.
Out for a kill, and shoot out are good consumers.
Utilities are Deadly Aim, Breaching shot, and your choice of Win-Win or Cleanup for the situational bosses in dungeons. Greater Good is okay, but normally a healer will carry it or not need it.

Shotgun/Elemental -
Powder Burn or Ignite are good builders. Eventually replace Powder burn with Striker or Ignite with Ignition.
Out for a kill, Flame strike or Blaze are good Consumers.
Utilities are Breaching Shot and Short Fuse with Cleanup being situational for dungeons. You definitely want to start putting your points towards the manifestations as these come into be a big help later on, specifically Electromagnetic Manifestation and Fire Manifestation.

Pistol/Elemental -
The Business or Ignite are good builders. Eventually replace The Business with Hair Trigger or Ignite with Ignition.
Shoot out, Flamestrike, or Blaze are good Consumers.
Utilities are Deadly Aim and Short Fuse with Win-Win being situational for dungeons. You definitely want to start putting your points towards the manifestations as these come into be a big help later on, specifically Electromagnetic Manifestation and Fire Manifestation.

DPS
There are many, many combinations of DPS weapons. In fact any two weapons can be a good combination.
For that, I'd suggest playing around or requesting builds.

or, TL:DR edition:

Sword
Builder: Blade Torrent; can eventually be replaced by Forking Paths if doing a solo or scenario build.
Consumer: Dancing Blade; Replace it as soon as possible with Chop Shop, Clearing the Path, or Steel Palace (best for soloing).
Utility: Martial Discipline and Stunning swirl, eventually replaced with Four Seasons, Trial By Swords, Steel Echo.

Hammer
Builder: Smash or Grand Slam are both good, but eventually you realize other weapons have better builders.
Consumer: Hell to pay. Replace as soon as possible with Molten Steel.
Utility: Stonewalled and Shockwave are both great utilities and can even be used situationally in end game content. Beatdown, Full Momentum, Furnace are great from the outer wheel.

Fist
All and all this is really best for soloing or healing. It's not strong dps output.
Builder: Claw is your only real option to start and even then there's noting else really good.
Consumer: Hog wild is okay. Savage is an okay consumer.
Utility: None that aren't for heals.

Blood
Builder:Boiling blood is good to use at first. Bloodline will be the eventual replacement.
Consumer: Bloodspike/Infliction is good to use for a long while. Bloodshot or Guts and Glory eventually replace them but you don't have to rush for them.
Utility: Cardiac Arrest is good for soloing. Plague and contaminate are good as well.

Chaos
Builder: Escalation if you're soloing, eventually replace with Run Rampant. Hand of Change if you're in dungeons. Still meh for builders.
Consumer: Schism is quite powerful until you get Pulling the strings, Cry Havoc, and Karma are all good.
Utility: Domino Effect. So great. Very Useful. Much powerful. Wow. Disclamer: only use Domino affect soloing or in scenarios . Discord Rising also.

Elemental
Builder: Ignite is a good go for starting. You *can* replace it with Ignition if you want or arc flash depending on the situation.
Consumer: Thor's hammer to start out with. Still useful later. Flame Strike, Blaze, Inferno, Fire Manifestation, Lightning Manifestation. It's all situational and you can pick and choose from there.
Utility: Molten Earth is beautiful to start out with. Cold Wave, Whiteout, Hard Reset, Electromagnetic Manifestation, Ice manifestation, or Overload. You just have your situational picks here.

Shotgun
Builder: Powder burn is good to start, Eventually switch it out for Striker or Scattershot depending on the situation.
Consumer: Out for a kill. This really is the best option.
Utility: Kneecapper works well into end game. Bombardment, Bomb Squad, Smart Bomb, Point Blank, and Shotgun wedding all have their uses based on what you need to do.

Pistol
Builder:The Business is okay. Try and get hair trigger as fast as possible if you want to build with pistols.
Consumer: Shootout is a great option. I still use it in end game raiding.
Utility: Dirty tricks is good for soloing. Gun-fu and Marked are also good as well.

         Assault Rifle
         Builder: Safety Off is okay, eventually replace with Hip Fire. Suppressing Fire becomes situational for  large amounts of mobs.
         Consumer: Fire at will is good to start. High Explosive Grenade is good for groups of mobs while Transfuse Anima is a good consumer as well even if you aren't leeching.
         Utility: Slow the Advance is great for soloing. Red Mist and Incendiary Grenade are good as well.