If you're looking for something fairly fast, but comfortable and able to go 800 miles in a day for not alot of $$, take a look at a lightly used, late model
(post-1996) Kawasaki Concours, though not for the shorter-legged. Not terribly customizable either, but they are a solid Japanese bike that you can work on in your own garage too (screw-type/locknut valve adjusters, CV carbs, shaft drive, etc.) or shop for a later model K100RT or RS.
If you're looking for something for more relaxed riding and a little less capable of triple digits speeds, look around for a late 90's or early 2000s model Moto Guzzi - they have old world style and panache, are fairly user-friendly and quirky like airheads, and the cruiser (California, Jackal) models will still out handle many other V-twin cruiser style bikes in the twisties, and you can bolt on many cruiser type accessories.. even a sidecar - as they have some significant torque to work with !
I've already got my Kawasaki, but my next bike will either be an R100 or a Guzzi as mentioned above, and a sidecar to go along with it.. without giving up the Kawasaki or the R65, if I can help it !!
