I like plain gauge but I’m of the larger persuasion and lack of corrosion was a big part of my choice as well. It’s worth testing some bikes, not just Ti, to establish the fit and ride you want, then seeing what marries up to that.
Unlike Cynic Al I wouldn’t automatically rule out something like the Yukon. It depends on your personal sensitivity, one persons stiff and all that.
At £3.5k you could get custom plain gauge, Burls, or direct to somewhere like Triton or XCAD, with high end finishing kit. Or you can get a higher level OTP or custom and go with medium level finishing kit.
Lists, I love lists, get making some to refine your criteria and narrow down the choices.