My only successful trip to work and back (20 miles one way with lots of up/down) took about 50 minutes each way...not counting the two other attempts getting flats and not having what i needed to repair and taking bus and walking etc.
The main problem for me is hand numbness from the vibrations. (had the same with my motorcycle..always the throttle hand for some reason). Gonna try metal shavings from car brake lathe packed into handle bar and siliconed shut.
The main thing, which I learned from mountain biking and being supremely self reliant because you're 30 miles from a living soul, is to be prepared with every tool and commonly (and uncommonly) failed part. Each time you have a mechanical issue, add that to your bag of tricks....like the time a friends clipless pedal cleat-to-shoe-bolt came out mid-ride, and 20 minutes later we mauled the shoe off the pedal, and had to mid-ride modify a screw from another bike part to get it so he could continue pedalling...now two of those tiny screws are in my pack. And V-brake pad pins from another ride, or brake cable from another one, or the solid-wipe-on bug repelant, or the New Skin spray-on bandaid for road rash (stiiiings!) etc, etc, etc. Learn from mishaps.
I easily packed everything into a medium sized Camel Back in addition to a 100 oz. water bladder and some high energy food and...herbs. (Note past tense!) Now I've got 2 pannier bags to stow lunch igloo and change of clothes along with bag o' tricks and feel oh so free without the backpack!