Before I get down into the crunch of it, I'd like to say two things. First, the reason you haven't had much feedback on this is likely because it's quite simple and extremely well done. There's not that much to say. Second, your spell table is messed up...and it's very distracting
Now, I like this a lot and might use it for a campaign villain. Pretty much everything is done well and it's still cool while being simple. It might be justified to either give him two domains or, and this is more likely, give him a bonus spell for domains. However, that brings him farther from being a gish and closer to being a spellcaster, which is a trap a lot of classes like this can fall into.
Other suggestions would be to make the skill points 4 which won't unbalance anything but will keep me from going over every skill description with a magnifying glass and highlighter in the PHB, and maybe giving it a d10 HD.
Regarding the minion, I like it a lot, but to me it doesn't feel very different from an animal companion/familiar. I'd say either allow the player to give it the fiendish or celestial template (which definitely won't make it too strong. Promise) or give it some SLAs.
In the domain section you might want to specify that the shrine warrior also gets the domain's granted power (I assume you want him to).