Biotics can feel so useless, maybe I am just bad?

You're using the Kineticist wrong is all. Biotic Ascension negates any need to worry about carry weight because as long as you keep it up your cooldowns don't exist.

I specced mine with Max throw force (rank 4) with pull gives me shield regen and +40% max shields while a biotic effect is active. Biotic kills give you shields back is also Very useful.

I use a sniper rifle to quickly build up Ascension and then everything without shields or armor simply becomes ammunition to throw at everything else.