ANT MAN
Particle Brawler

 Ant Man was one of the first heroes that I leveled because I loved the way his powers looked and felt. The film did such a great job portraying a potentially goofy B-lister as a powerful super hero. I felt the game captured this as well. I never did like his ant power tree though and I preferred to bounce around the map punching people with my tiny fists. When I went looking for a build I found some similar ones, but nothing that fit how I wanted to play him, so I ended up just going with a more "particle brawler" focus with a few ant powers to proc buffs, etc.

This build is meant for fun and not necessarily fastest clear times. I have been able to easily complete cosmic trial with this, as well as do any cosmic terminals. I mainly like it because the animation of bouncing bullet, flying around the screen destorying bad bad guys, is awesome. Recently I've done raids with Ant-Man with no issue whatsoever. This is a really tanky build that still does decent damage.

POWERS and ROTATION

 Tiny Takedown is your main spender against a single target. It might not appear to do great damage, but at around 5-6 attacks per second it adds up nicely.
 Bouncing Bullet. Yeah, I know it isn't the greatest DPS, but jump into a mob leading with this attack and you spawn ants really fast. This allows you to apply your dot quicker and use your bursty one-two punch. I just love this power, despite its mediocre damage. Bouncing around and punching a bunch of bad guys is what makes Ant Man fun.
 Red Hots are your main damage over time power. Apply liberally to mobs after several bouncing bullets. It buffs your damage with Tiny Takedown as well from the first row talent (Set 'Em Up, Knock 'Em Down").
 Inch High Goodbye is one of your burst dmg powers, as it has an execute.
 Fist Full of Ants. Your second and last ant power. Use it after Inch High Goodbye for a massive damage spike, especially with "One Two Punch." This does damage in an area and can also be useful for taking out some medium difficulty mobs.
 The Definite Particle does solid damage as PBAoE, as well as a huge buff to our shrink powers with "The Particles Must Flow."
 Big Foot Sighting is obviously a real heavy hitter that also buffs our health for a short time. Pre-BUE we were able to keep this buff up indefinitely, but I haven't tried stacking enough power duration gear to do so currently. Another really fun power.

The rotation is usually:
 several times for trash mobs. It doesn't take long to bring them down. But for harder mobs you use this to build ants quickly before:
  -->  to several enemies -->  pick one to focus on -->  --> -->  several times if you need ants (otherwise start back with Tiny Takedown).
For bosses or spongier foes, add  for extra smashing.

GEAR

I put this together mostly pre-BUE, where lots of tankiness was needed to complete the cosmic trial. Even after BUE, I've found that being able to facetank 90% of enemies extremely useful and extremely fun. So I generally stack speed for extra dodginess.

Artifacts
 Scrull Communication Device. BiS for Ant Man, as it provides both speed and stacks of intelligance (while in combat)
 Lizard's Formula. Adds damage, speed, increased attack speed, some energy management, and a rez.
 Crossbones Teaching Credentials (INT). A generally good artifact that has lots of nice stats. (for some reason it doesn't show the cosmic affixes here)
 Black Cat's Grappling Hook. I use this because of the Speed increase and bonuses to CHR/CDR. The movement dmg buff is rarely used (wouldn't it be great if bouncing bullet was tagged movement?).
Everything can/should be swapped out for their cosmic versions.

Alternatives:
 generally good for melee heroes, 
 generally considered BiS if you are stacking INT, might replace the grappling hook with this
 always a good choice

Slots 1-5
As I generally like to keep my builds easy-ish to obtain, I use his own uniques. Fragment of Twilight and Cobra's Hood are other uniques to consider.
, 

Peripherals 
 Doom's medallion because of power duration. It will keep the definite particle up, well, indefinitely. Alternates are: 

 Insignia of Mockingbird for the increased attack speed.

 The Power Doop on physical Uru. Adds brutal damage and some energy management every 17 seconds.

 Shield of Perseus. I currently only have the level 70 version, but the extra tankiness is very helpful and you'll actually proc level 5 quite often, which is nice.

 Relic of Atlantis. Often considered the best general relic for damage.

 With +3 INT and +3 SPD. I happened to find one, so I used it. You can also use the Sling RIng here as it provides lots of goodstuffs. 

NOTES

Use your infinity to buff speed, intelligence, defense, and life on hit.

Wasp Teamup mainly for lore, but she seems to do decent damage. She also rarely gets stuck if you are objective rushing, which is nice.

Remember, this build is mostly for fun, watching him bounce around the screne and destroy people. It is still very effective, even if it isn't the fastest TTK against a dummy, and you can clear any content with it. Well, that's it. I hope you enjoy Ant Man as much as I do.