Thank you for taking the time to explain all of that. There were certainly a number of things I was failing to take into account, the bottom bracket height being one of them.
Incidentally, yes, my New Yorker has the old swept-back cruiser-style bars on them. What's more, I plan to put the same style bars on the road and MTB frames; I just need a good upright position.
I guess ultimately trial and error will be the only way to truly find out what will work for me ... if I buy a bike that isn't right for me, it won't be the first time

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