do you need to use those psi powers?

[Padischli]

you can unlock those psi powers but would i be fine just ignoring them? i would rather spent my neuromods on the normal abilieties i hope you guys can help me!

[Apoc]

You are not forced to. You could even finish the game without using any neuromods at all.

[Fodax]

Psi powers are EXTREMELY helpful, however if you want to do a "human" run then no you do not have to use them. To get access into extra rooms you will need the psi morph ability. Getting 3 abilites makes you detected as a threat to turrets but you can hack the turrets to be friendly again.

[OKMB]

Some enemies are really weak to psychic abilities, doing massive damage in lieu of weapons like the shotgun or pistol. It's worth it to nab Psyshock for Phantoms, or Mind Jack for Telepaths.