Heck of a start folks, thanks very much. Other issues have predominated of late, so I haven't gotten any further than this as yet - I'll post whatever I find as I find it, I guess.
I do agree that whole house is an audio orphan, though - how else to explain how few options there appear to be? I also agree that in-wall and in-ceiling speakers are probably not where we want to go, but Bro has concerns re: layout and furniture placement flexibility. Nothing insurmountable, I shouldn't think, just have to strategically place outlets as needed - but since he keeps changing the floorplan right now, we may be here a while. I agree about the mini-monitors, but think we might be looking at a high wall mount instead of stands - sorta using the ceiling for the floor in a traditional application. I've only done that once, with outdoor speakers in a hot tub room; though they weren't audiophile grade by a long shot, I did get adequate separation and reasonably balanced tone, though obviously not a "soundstage" to speak of. I spent a grand total of 15 minutes setting them up, too, so it's hardly a fair fight, eh?
As far as the budget goes, he's a big city lawyer (don't think I don't choke on that now and then, but...he's still my brother :-)) and is completely willing to spend like a drunken big city lawyer - so I think this is going to be fun! (Unless I do the reasonable thing and take Dekay's suggestion - then it's just another contractor to deal with and we'll probably get wonderful sound everywhere - but where's the challenge in that??
chas