The thing about one IC title and one US title if they kept both is they need to define the divisons.
WWEWHC - Orton, Cena, Batista, Brock, Trips, Taker, Rock, Punk, Bryan, Kane
IC - Langston, Sheamus, ADR, RVD, Jericho, Mysterio, Show, Henry, Reigns, Wyatt
US - Ambrose, Miz, Kofi, Fandango, Sandow, Wade, Dolph, Rollins, Sin Cara, Christian
I think all 3 belts can be sustainable with proper set divisions, but that they can't have two equivalent belts. Instead of unifying them, I'd be all for a show of champion vs champion with pride on the line, and then them just defining the divisions and who is chasing each belt.
The way I set it up sees the top of the card look like the top of a card, and is what the undisputed title needs for a year or so. The IC title is filled with former world champs thanks to the WHC debacle after edge retired, but it adds so much credibility at least when you used those fluffed resumes to put over Wyatt, reigns, and Langston vs those guys. The last division is youth filled, but it has 3 former world champs in Miz, Dolph, and Christian. That's what I would do, along with still keeping the tag division a focus
I man who are wee kidding? If one gets scrapped some Cruiserweight title will pop up, so just say fuck it and create a sustainable division