Alright, so I'm making a samurai-esque character, ex-Blades, and I'm going to have him become Thane of one of the Holds, serving only that Jarl. So first off, can you become Thane of all the Holds? Which one do you think I should choose? Whiterun is out of the question, as it requires you to be the Dragonborn. Also, which race do you think would fit best? I'm thinking Imperial, but I'm open to suggestions.

You can become Thane of all the Holds.

I think you should choose Solitude. They have the closest ties with the Empire, and the Empire has the closest ties with the Blades. (Along with being Dragonslayers, they served as the Emperors Guard or whatever you want to call it)

Imperial or Nord.

You can be Thane to all holds.

I think the best fit would be Markarth, but three others might work, Windhelm, Morthal, and Solitude, somewhere a samurai might be, because, Riften is to crooked, Falkreath is to out of place, Dawnstar is too small, Winterhold is too small aswell

Dawnstar is too small, but Morthal isn't? Not sure I understand your logic, but okay.

I guess your CW allegiance should factor it. Friend toward the Empire, or friend to the rebela?

Well I suppose that would depend on which Jarl I choose to serve. My character will be loyal only to the Jarl he serves.

i didnt say that it was big enough, i said they would work, just something about morthal makes me think honor, i just dont like dawnstar, maybe? But yes morthal is small, it just has personal appeal, maybe because of the quest surrounding the burnt home?

Riften.

Because

Riften