My ride requirements are much the same as yours, but I'm not your size. I'm 5'9" and 157 lbs.
I have a Trek Soho DLX on order at my LBS. It should be low maint. with its internal hub gears and carbon fibre belt drive.
I plan to take the fenders off, and will be riding it on our local Rails To Trails and the mostly hard pack canal trail.
No matter how dirty it gets all I will have to do is rinse it off with the hose, and no lube required.
The bad news is it's not expected to come in until sometime in November.