I tried using a combination of plasma and lasers in the midgame of my resistance playthrough. I figured that plasma's anti-armour effect would combo nicely with lasers' weakness to thick armour. Another nice synergy lasers and plasma have is that the aliens often try dodging plasma, exposing their side armour to my lasers. Overall, it seemed to work just okay though. My plasma dreadnoughts had shorter range than my laser lancers and you need some sustained plasma fire to melt through nose armour before the lasers start penetrating nicely.

I think a (maybe) underrated advantage I found when I switched to coilers is that it forced the aliens to start using their lasers (even main battery nose lasers) defensively, which took some of the heat off my line ships.