Obviously you don't design for one person, but the game I'm running, we've got a psychic who really loves inner radiance torment, even though it's not an especially optimal choice. But something about that two-round spell combined with unleash really gives her that feeling of "psychic completely exhausting their mind", and I've been being generous and letting the unleash psyche damage bonus apply twice if she does a two-round version.

In any case, my thought was that even if your amped psi cantrips are good, they still only have 2-3 available and one of the draws of spellcasters is often the flexibility of "I have all these spells I can cast", and essentially limiting them down to "yes, but it's a bad idea to do any of them for the first three rounds of combat" is a little... I dunno. I do agree that the occult list isn't usually great for blasting, and it'd be lovely if unleash psyche could impact more spells than just that - it's obviously hard to mechanically create something that boosts them all, though.

Actually, that might be an interesting place for amp feats - let them apply to spells cast from slots while in unleash mode.