are you doing a fresh insanity run or new game plus?
anyway, you'll grow into it. Don't forget that by the end of your first run you most likely had all the health and weapon upgrades. I'm late game in my second playthrough and it's pretty easy again (only hardcore...geth rifle is awesome, btw).
also, is overload that useful? warp seems to be just as good and serve more purposes. I keep seeing that respec sounding option at the upgrade booth and might take away overload in favor of maxing out throw, warp, and warp ammo.