Yes, a lot of times. Classic is easy because you getting access to advanced weapons early, same for MC Lab. No no line of sight penalty, so you can shoot throw entire map. Fast getting Mantas and oscillators. Most of missions could be skipped and all USOs just shut downed by Mantas to maintenance good score. Annoying 2 stages missions could be skipped just arriving and aborting mission. Half of negative score, but better than full minus. No hunter killers. Aquanauts with 90+ MC strength couldn't be controlled at all. Game can be finished in 3 hours on maximum difficulty (no I'm not speed run it, just saw videos). I understand what you made mod to long play, I just bad at it.
Btw, medic unlock for me calcinite corpse, but no drills in research list, and main question now - can I research another corpse manually or it's no longer possible? If Barracuda destroyed pilot gone forever?