I went with a melee build and it was a LOT of fun
First went up against Collectors with a Claymore w/ Omni Blade & HVB. The cooldowns were fine during a solo test, but in a friend's lobby, they became horrendous. I don't know why the discrepancy, but it happened. It was only a problem when I got the off host cloak glitch.
Anyway, I'll have to do a solo vs Collectors to get more data, as most of my targets were being shot by teammates while I was engaging.
Next match was in Reactor vs Cerberus. It was wide open enough to be on my own for some good parts. I also brought a Wraith w/ HVB & OB + Acolyte for the cooldowns. Still did substantial damage with the Wraith + Incendiary Ammo (even though TC Weapon Bonus is bugged)
With Fitness' rank 5 bonus triggered, a Heavy Melee will:
Kill a Dragoon outright
Take a Phantom to 2 bars of health (shoot then melee to kill. Warp will sometimes trigger DR animations)
Take a Centurion down to 2 bars of health (warp first will kill)
Kill Nemesis & Assault Troopers outright. I believe Engineers, also.
Take about 3 bars of an Atlas' Armor (was doing a Cloak, Shoot, Warp, Heavy Melee, Shoot combo to great effect)
It is very rewarding to watch everything flyyyy
Build was 5/0/6/6/6 (I'll put maybe 3 in DC later on). All weapon damage in passive.
When I'm satisfied with how much I've played with this build, I'd like to try a 4/6/6/6/4 build with a Claymore + Warp Ammo for the DC, Shoot, DC Transfer, Shoot, etc
For bosses, maybe Warp first to debuff, shoot, DC, shoot, Warp BE, shoot. I don't believe too much could withstand that, especially once TC damage bonus for weapons is ever fixed