Sorry for not being online for a while, got only now your answer.
I actually was under the impression that Sectopods were "fixed" to use plasma weapons in vanilla Openxcom, I guess I didn't check that....
Once you hit the personal armor tier, soldiers get more "proper" wounds that require some 10 days to recover, and die far less than before that tier. Good plasma shots still are dangerous, but no way you get insta-killed like w/o, and with power armors you get NO insta-kill, but the occasional bleeding that kills the unfortunate lone soldier that gets no first-aid in time.
The small launcher still gets some guys knock'd out occasionally, and the Blaster launcher seems a bit nerfed cause concussion damage is effective only on the explosion tile.
My soldier pack is quite the steamroller right now, thou again ....last game wa more than a month ago and I'm not on superhuman.,,,,will fix that tough through savegame editing once I get the chance to play again...you might not believe me but I really have close to NO time.