D&D would not be my choice in such a game. D&D is about zero to hero.
Eh... I don't think I agree. It might be fair to say "D&D has
become about zero to hero," but that wasn't always the case and is not baked into it.
When I was playing AD&D, in college, one game ran from 1st level to 4th or 5th level over the course of the school year. The next fall, I ran a "sequel" campaign that took those characters to maybe 8th (depending on class XP table). We gamed pretty much every Saturday from noon to midnight, so each of those blocks would have been akin to roughly two and a half years of weekly, four hour games. That's slightly slower than one level every third month. 5E players would be looking for pitchforks and 3.5E players would get creatively morbid. But, it was fun. No one complained. Honestly, I still don't like playing past 10th level or so. Really, the high level spells make the game less fun, for me.
I also get annoyed that it seems like players get new toys faster than they can become proficient in what they have. AD&D had a
lot of creative uses for low level spells. Later editions have pretty well purged any side effects from things, though. 5E loosen up a bit from where 3.5 and 4E were, but there's definitely still some restraint, there. The topic could be a whole rant thread/edition war on its own, though, so I'll leave it as a simple statement.
Still, I'm not sure I'd be thrilled with
zero advancement. I do like to see characters grow and change over time. But... if I boil it down to the original context -- the length of SKT -- then I think I'd be fine with no advancement. The "sweet spot", for me, is probably one or two levels over that span, but only advancing through items and learning tricks with what you've got would be at least as fun as doing 1-11 over a few months.