Right now I'm contemplating an Ultima VII run with Exult (it smooths out the stuttery gameplay that DOSbox leaves intact),
Funny you mention it because I've been casually doing just that the past month or so with my GOG copy. It's a breeze to get running with Exult, which just makes things so much smoother overall. I also admit to being spoiled by the increased resolution/display radius even if it's regarded as a cheat, and have no apologies. =p I could never go back after using Exult.
Still one of the best open world RPG fixes you can get. It's massive in size, hours and interesting things to do, and has cool secrets tucked away everywhere (something I sorely miss in RPGs). Plus you actually have to use your brain; no chasing arrows on your compass. Had someone from GAF message me on Steam and tell me I had good taste when they saw me playing it, but I can't remember who it was. Serpent Isle is just as worthy, even if more linear.
As far as the Gothics go I agree with you; if I had to replay one or choose one to play for the first time it'd definitely be the 2nd.