Let's do 3 skills in the game: combat skill, medicine skill, support skill... officially you don't have to tag anything, everything is automatically distributed during game so the simple, casual minded player doesn't have to think. Now that we covered that, let's move to s.p.e.c.i.a.l points. There will be 3 of them: stamina, intellect, dexterity, obviously you can't raise them, but only in game items give them in game that only takes just about forever to get, to make sure the player has next to no choices and he can't possibly do wrong...
That is to what all the suggestions to merge something lead to when players over-exaggerate with the convenience of combining something.