Bio plasma is a dangerous thing to use. Your opponent might reduce the casualties from base contact, and if he manages to remove enough of them then you can lose your normal attacks since base contact is checked for again when they are due. I'd consider dropping it, or changing it to implant attack (which won me more than one game so far)
Extended carapace is a mandatory upgrade for warriors! It doubles your resilience against bolters for almost no points.
Leaping warriors also always should have flesh hooks, they are a great deal. Initiative adrenal glands are almost mandatory too. Toxin sacs and weapon skill adrenal glands aren't that expensive either. Heck, considering the base cost of a leaping warrior with must-have upgrades almost all biomorphs are cheap.
I strongly dislike shooty warriors, but if those swarm warriors work for you, then that's fine. My guess would be that they'll fail you horribly though, at least against marines.
The infestagaunts are fine, toxin sacs might be worth considering if you go against T4 stuff.
Swarmagaunts are commonly called spinegaunts...gener ally scythegaunts (no upgrades and scything talons instead of spinefists) are more effective though.
Those executioner warriors are interesting...keep them faaaar away from the enemy. In case of these extended carapace might not be necessary, as most weapons with a sufficient range to hit them will have AP4 or better anyway, but if you have some points to spare you could take it nevertheless, just to be sure.
Some lash whips mutants will be priceless.
jwu