Rew,
That's a really interesting question, not least because I personally believe that what amounts to being 'comfortable' has in the main radically changed over the years. Arguably partly inducing a big revival in the interest in both classic and vintage motorcycles as their designs were more favourably disposed towards true comfort. But of course that is not the only reason for such increased interest.
For perspective I should point out that during very early mornings in the 1950s (when winter weather was immensely more severe) , six days a week, I heard my late father set off for work at the steelworks often in deep snow, howling winds or driving rain. Motorcycles and push bikes filled the early morning roads in those days being a working man's transport. Had he still been alive he would have replied to the effect that no motorcycle is 'comfortable,' if it doesn't have both comprehensive leg shields and full screen. He would have taken a comfortable seat for granted. In those days only management owned a car!
For me 'comfort' also means that on any new bike I don't have to go to the trouble of having wheels and frame repainted, or additionally as I recently further undertook on a GTR1400, extending one or both so called 'mudguards' with cut down mudguard extensions from a bike thirty years older!
Being into road biking for fifty five years naturally I've owned many bikes, including extreme sports bikes and plush tourers. Had I to name the most 'comfortable' of their number (but excluding extremely large tourers / cruisers) I would unhesitatingly vote the Kawasaki GTR1000 as winner. I was fortunate to own three over several years in the 80s, so impressed was I by that model.
But Rew, if your biking will largely be limited to sunny days my extreme but practical views will not be quite so relevant. Have fun searching!
