Given your criteria and physical dimensions, doesn't seem that there is a need to spend for custom titanium frame.

If your riding style is more out-of-saddle-power; you may benefit from an upper-end titanium frame with shapely tubes that offer directional compliance & slight better power transfer.. but a decent pair of wheels and tires can do that, too.

If you can afford it, try a budget ti frame for a few years, they can be found under $500-600.. If you enjoy the ride, then find a higher-end ti frame for long-term.

Personally, the allure of titanium frame is no need for upkeep.
I ride my bikes in all weather, rain, snow (salt), mud and I rarely clean my bikes.
No paint to scratch or chip, no cleaning needed for ti frame to look good.