In Oblivion it was made very well , the Champion could be any race.

The Nerevarine was always an outsider, even when you played as a Dark Elf you weren't considered a Dunmer and the people considered you an outsider so race made no difference there.

In Oblivion there was literally no difference at all, which made sense considering the location you were in.

I would say that Nords make the most sense based on a shallow look at the lore, but Martin Septim for instance was a dragonborn and he certainly does not fit the typical idea of a Nord warrior, he wasn't even a Nord. We have evidence of Dragonborns from many nationalities so there isn't a real problem.

My point to begin with wasn't really who was suited best for the MQ.

Saying that Skyrim was "designed" for nords is wrong, because there literally isn't any difference between how the races are distinguished in Skyrim; which truly is a shame. I really wish they would add that depth, but sadly they didn't.

Since all the Septims were Dragonborn that also means that there was likely one that is elven as well. There was a Dunmer Empress for a period.

Empress Katariah, yes. She was a Dunmer and from as far as we know the Dragonfires were lit during her reign meaning that she was a dragonborn too.

Which mean we have Nord, Imperial, Dunmer and half-elves covered. Not sure if there were Emperors of actual Breton decent, but Katariahs son was half-Dunmer, half-human. Men and Mer have proven lore on the matter(and since you can be a Beast race Dovahkiin in Skyrim they technically do to), the beast races on the other hand is more unknown since they have no known Dovahkiin except the Dovahkiin.

Not a fan of Nords at all, so I feel perfectly fine playing other races, particularly Bretons, Argonians, and Khajiit.

I cannot relate to people feeling they need to be Nords. Why would a Dragonborn need to be a Nord?

Nope, never played a nord. To me they are the most boring race as they are most like earth humans.

And thats why, if you play a smart nord, you'll be one that has miraculously broken the chain of stupidity to advance in intellectual capacity. And thus, having a selective advantage over all your other dumb bloke nord brothers, women will automatically flock to you like bees to honey, and you'll have lots lots lots lots lots lots LOTS of children.

And of course, lots of something that happens before you have children, heh heh.

Maybe because of the Dovahkiin Nord dude used in all the marketing.

I forgot about all that iconic goodness.