*raises hand* I'm a 53 AR/Dev blaster and I have no other 50's. I've been playing since beta and have seen many iterations of blaster over the years, including the dark days of defiance 1.0.
You need me. Now more than ever you need me. I'm the one who solos crates and containers in Lambda while you all split up in random directions for whatever reason.
You need me to plant mines in intelligent places and times, so that Maraurader lands on a dozen of them when he jumps to that round bunker thingy.
You need me to throw Caltrops all over the sidewalk to slow down escaping prisoners during the BAF, which my AoE will tear apart.
You need me to hold back the flood of reinforcements coming to help Nightshade and Siege while you try to learn how to do damage, switch targets, and look at two health bars at the same time.
You need me dart around the Reactors, plucking power cells and quickly luring mobs away from terminals or simply knocking them all off the platform before Anti-matter gets back.
You need me to do more damage than the disintigrate heals AM for because the healers can't find the giant chat bubble that says "HEAL ME".
Could any AT do one or more of those things? Sure.
Could any AT do ALL of those things? Only one I know of.
DISCLAIMER: The previous rant is not to be taken as a factual statement, only as self-satisfying puffery.
To me that sort of implies that was the dev's intention in leaving build up out of the devices powerset. It's really always seemed more of an unintentional side-effect than anything else to me. That would imply that they planned defiance 2.0 somewhat around the devices powerset specifically and I don't really think they did that.