Houston and Cincy were missed opportunities for the ACC. Both would have fit well.
I think these opportunities are very much still on the board if Stanford, Cal and SMU are added. That gets the ACC to 17 with a high likelihood of eventually adding a minimum of three more teams that are suitable geographically for the western flank. I think the obvious strategy here is to end up with either three divisions of 7-8 teams or four divisions of 5-6 teams.
The goal is to be the third best conference approaching the end of the Big 12's media deal in 2030-31. If the ACC has higher payouts and more stability it can poach the best of the Big 12 at that point, assuming the B1G and SEC don't want them.
For now, ignore the likely departures (FSU, Clemson, UNC, UVA) and assume that if they leave they're backfilled with the best available schools that sort of match them in the footprint (UCF and USF come to mind).
EAST
Syracuse
Boston College
Pittsburgh
Louisville
Virginia
Virginia Tech
Clemson
SOUTH
UNC
Duke
NC State
Wake Forest
Georgia Tech
Florida State
Miami
WEST
Stanford
Cal
SMU
Houston
Utah
Two of: Arizona State/Arizona/Kansas/TCU/SDSU
If you want to go bigger and really finish off the Big 12 (what they should want to do), you add Cincy and WVU to the East division, drop Clemson into the South, and take three of the schools on that last line in the West.
You now have a clear #3 national conference with geographically cohesive divisions, strong brands, a lot of like minded universities and good coverage of most major metropolitan areas. You also have a good assortment of private schools with powerful alums, and major public universities with political sway due to receiving taxpayer revenue. That also makes it harder to get left out of future playoffs when the dust settles on realignment.
You also maintain optionality to get ND along the way somewhere. It's super unlikely, but leaving that seat open for as long as possible is necessary because it cements you as a permanent power conference. The way to do it is to go to four divisions instead of three, thus opening up more cross-divisional rivalries and allowing them to set up the exact annual schedule they want.