Looks good from here, any restrictions, what sources you can use for this?
How does your friend feel about summoning?
Yes, I mean something like Thaumathurgist 2/ Malconvoker at least 5/ finish however he likes.
- Can already cast lesser planar ally
- Thaumathurgist does need Spellfocus: Conjuration, but gives Augment Summoning at lvl 2
- Church Inquisitor 1-2 should take care of the skill requirements for Malconvoker
Thematically Water Devotion would fit, if you have Turning left to use it more than once/ day.
Don't exchange the domain, just take it with a regular feat if you want it.
If you want to invest into a quickloading Crossbow, with Knowledge Devotion & Zen Archery the ranged damage output should at least equal the Soulknife(that is, if the Homebrew part didnt make him better at throwing his mindblade).
I'm not sure how he feels about it. I don't think I'd recommend Thaumaturgist, anyway. I never really liked the class. At this point I'm pretty much satisfied with him picking whatever PrC he wants. If I were playing it, I would probably take the Plant domain at level 1 instead of Water, and then pick up Water with the Contemplative level. That opens up the full 10 levels of Holt Warden as a potential option, which is a class I personally rather like. If my friend can somehow swing an Animal Companion (how he'd do it I have no idea), then the Wavekeeper PrC opens up and gives some really useful options if this campaign is going to be featuring a lot of underwater action.
Also, I agree. Between Cloistered Cleric and Church Inquisitor for at least 5 total levels, there should be more than enough skill points around to max out Heal (at least up until this point, for Healing Lorecall) and Knowledge [Religion] and still have plenty left over to invest in various Knowledges for that Devotion and to satisfy whatever pre-reqs he needs for other PrCs.
Remember that you don't have to switch out your knowledge domain for knowledge devotion, but can use Inquisition domain for that when you get it (and you would rather like all knowledge skills than +2 to dispel attempts).
It's actually +4, but I think switching it out for Knowledge Devotion would still be a substantially better idea. My friend initially had it on his sheet, anyway, but my suggestion is switching that out for Divine Spell Power (everything else was his idea). What's more, without Divine Magician to get the really nice Dispels or many consistent CL shenanigans to max out their bonuses, that +4 bonus isn't *that* awesome.
Another note, with Knowledge Devotion on the table again, if Healing Lorecall isn't doing it for my friend, I'll suggest Lore of the Gods to him instead, especially if the DM gives him the +10 bonus.