Ah, I guess I didn't elaborate sufficiently (or, really, at all) about character concept.
Yes, a monster-hunter inquisitive (e.g. van Richten) would be an appropriately thematic Inquisitive. However, I'm envisioning somebody interested in secrets: objects, knowledge, books...or just poking his nose into places where he shouldn't be. He's a rich (noble background) dilettante who spent his inheritance on this pursuit, and he just gets a high from finding out what he's not supposed to know. ("So that's what an Elder Brain looks like. Cool. Ok, what's next on the list?")
I did look at Knowledge Domain, but it's the whole relationship with a god, or being a representative of a god, that seems off. He's cerebral, not religious. So, yes, the abilities are thematic but not so much the class concept.
Refluffing a Cleric as Psion does make sense, somewhat. I suppose it would depend on somebody's boundaries of how far they are willing to re-fluff.
(Picky, aren't I?)