I've used the majority of them, short of the vault ones anyway and here is my pick of the weapons for PVE.

Primary: Devil you know hand cannon.

I've used all the exotics/legendaries and frankly, broken them down for parts. The DYK is EXCEPTIONAL for it's stability and impact. It's like a mini rocket launcher. Easy to handle, stays right where you left the aim, IMO, far and away the single best primary.

Special: Kinda torn here but I'm going with the Icebreaker/Patience & Time combo for snipers. I like both, no two ways about it. The obvious arguments are going to ammo and range.

While the Icebreaker wins hands down with the range and ammo regeneration, the P&T wins hands down with stability and rate of fire, especially after you get the field scout perc.

Fusion rifles: Torn between the Plan C and the Pocket Infinity.

Arguments: Charge time, rate of fire, magazine size

Both are situational and very important which is why I take them together for alternate situations.

The Plan C by far has the better charge time, range and magazine capacity but at the same time, once you get the Pocket Infinity perc, um, talk about shredding bosses at medium to short range, just whoa. Also makes the 2 or more enemies with one burst bounty hella easy, just sayin'.

Heavy: Deviant Gravity machine gun for me. Excellent rate of fire and stability play awesome impact. Not even close on any other machine gun imo.