My main and first and only play through thus far have been an advance prototype. I'm a bit confused by the question. also this is the first time I've heard pyrotech was the croud favorite. I felt since it was usable in both advance classes it was the lame one, I chose powertech AP because it was the purest Powertech DPS. Also like the skill tree better. Maybe I'm missing/missed something though. I like Powertech though because its more run and gun. If i wanted timed attacks and no movement I'd be a agent.
Hope I contributed