I understand what your saying, I just don't get the why. I mean, we all have our favorite systems, but you make it sound like its hard to run a social game in 4e. I mean sure, 4e has a lot of combat effects, but how much stuff do you need to run a social game?
I'm currently playing a fighter in a 4e game, and he has almost the best strength you can afford. I also have a 14 cha, and diplomacy as a trained skill (I took the warlord multiclass). I am full capable in combat, yet I have excellent social skills.
So what other rules do you need to make the social game happen? Lots of classes make great use out of charisma already, rogues, paladins, warlocks, inspiring warlords, etc. They can all pick up diplomacy and intimidate etc and be great in combat and social scenes.
I'm sure 4e would support a primarily social campaign just fine, I'd merely prefer something with much simpler combat rules if there isn't going to be much combat.