I remember an old show called Tiny Toons, where Babs Bunny would say, "Do you like my ears up or down?"; I think that an alarming number of those character permutations are so close to each other as to be insignificant.
I also remember Todd Howard mentioning Fallout 3's 200+ endings.
I think your initial concerns might be more valid than you think (in practice, as opposed to theory).
Perhaps, but even the change in just 1 skill choice can make a difference in overall gameplay style and RP. My characters are so specific that even such a small chance does make for a completely different character.
For instance, of my 10 skills, well, the 7 core ones are in my signature. But I may also want to do a bit of leveling with Alteration, Sneak, and Marksman (all additional skills I'm considering)
If you take my 10 skills of 1-handed, Heavy Armor, Conjuration, Destruction, Restoration, Enchanting, Smithing, Alteration, Sneak, Marksman, and take out even one of those skills to replace with something else, it could possibly have a significant change on how the character plays.