Personally, I'm willing to wait a year or two for these sub-systems to come out, but I'd like to be an important early priority rather than a late product cycle add-on. Individually, this subsystems can be very specific, but together they enable a wide range of campaign styles. As Lord of the Rings aptly demonstrates, epic fantasy battles are a staple part of the genre and should be supported by a game like D&D. Even traditional adventure-focused campaigns can benefit from allowing the PCs to participate role in the great battles.
-KS
I don't think I could say it better than this. Well done!