Don't underestimate the power of the charisma-tied skills like Speech and Barter. I've had plenty of checks against these...
EDIT: It's an entirely artificial limitation. This was modded all to hell in FO3.
Things just tend to get crowded when you have more than that around you.
Barter isn't that much of an issue, there plenty of fodder to pawn off. Speech, I just tag and dump the first few levels of skill points into with a high Intelligence score and compensate thoroughly. And since the FPS aspect of the game cripples the reason for high weaponry scores, you aren't shorted much from redirecting skill points into non-combat skills. And things wouldn't get too hectic if it wasn't for the AI's default move to charge into combat after an enemy and then move onto the next one... despite being told to stay close and passive. (I don't think those options actually work.) Rule set, context sensitive, and multi-state AI design must be a foreign thing to the developers. Then again, the game engine might simply be too worthless in this aspect to offer much to developers and modders alike.
Oh well, hopefully modders will take care of it. It seriously feels like Bethesda and Obsidian are taking a few pages from the S.T.A.L.K.E.R. playbook: Release awkwardly constructed game, let fans straighten it out.