I understand the underlying concerns here, and while I almost wish I hadn't brought it up, I'd also hate to think about it mid-game and try to change things.
For this game, most skills will remain the same. Occasionally, if something comes up such as a potential knowledge check, I will alert players if they get a particular bonus for familiarity before the roll is attempted. Certain rolls will not be necessary, for those things which are common sense or otherwise common knowledge (such as identifying a creature that is part of one's own race, or is extremely common). Similarly, social opportunities will be met with a bonus or penalty given the circumstances.
Honestly I'm not sure what route is best. I don't want to over-complicate things. I also want you guys to have fun. And you guys want to be able to start soon. I'll try to take a better look at my options, but for now I've got some homework and classes tomorrow to get through. Tomorrow night if I'm not too exhausted, I'll be in a better position to weigh these things against eachother. I will say that I generally like that the linked Diplo rules describe Diplomacy as bargaining. It's not a perfect system but the description is apt.