Building a house

About the only thing I would do is make sure you have plenty of outlets. Things change over time so installing anything in the wall limits future choices.

Thanks, plan to have a bunch with dedicated outlets for the mono amps. Of course will be doing professional sound treatment after the room is built. Have used vicoustics in my current room. Any other suggestions?

+1 to Russ' comment.

Separate electrical circuits. Ethernet of course. Look into "Rockwool" or similar sound insulation techniques and see if that is of interest.

--10g dedicated line with quality outlets. (Unfortunately some codes require crap safety outlets so you may need to swap these after inspection)  
--if using led lighting, place on a separate line.  Carefully consider lighting options. Ceiling cans are nice for task lighting but I do not like them for when I listen to music.  Have some nice accent lighting options.
--carefully research room dimensions and where you anticipate speaker and listening chair placement.  Can be hard to predict but clearly some dimensions will have fewer standing wave problems than others.
--do you want windows?  I opted out as they are not nice acoustically and I wanted to achieve acoustic symmetry as best I could.
--suggest double dry wall with a layer of "green glue" adhesive
--Crown molding in acoustically your friend.
--Use a solid, heavy door to the room and a seal on the bottom is suggested as well.