From my experience the Engineer filled the roll of resource collector better than everyone else. The turrets if placed well enough could avoid the rpg mechanics and the shooter mechanics while thumping. Basically just free damage, it made thumping less interactive or challenging.
Firefall needed some resources sinks badly and the opportunity to turn destructible turrets into one was too great. Everyone should be able craft and place turrets, while Engineers could fill a role of maintaining them. The whole thumping scene should be tuned around the risk of damaged equipment or even total destruction.
This game can't use tank, damage, healer like in traditional MMOs. However relying simply on twitch mechanics for PvE won't hold an audience. Interdependence is key for an MMO otherwise you'll just try to solo everything.
You can't have tanks, what would he do.. jump in front of bullets all day? No threat mechanics to protect damage dealers. Healers are pretty easy to introduce, but pure healers? Unlikely.
This game is going to have define roles to play while also shooting bad guys.
Our main tanks? Obviously a thumper (or some other machine.)
That means... we get two healers. Engineers and your Biotech archetype.
Engineers would heal the main tank, avoid getting shot, all while also getting to shoot at critters.
Biotechs would heal everyone (and shoot.)
There is also a third unexplored role in FireFall, some sort of hard crowd control.
Every class, frame, or role has to have a highly effective way to deal damage while also having the option of a secondary role. I'd say having no pure damage role, that way each frame gets an interesting set of options if they focus on damage.
