You're on the right track. Americans are obsessed with road bikes; you don't have to be. Make sure your lighting will last 90 minutes or so for your distance. I'd run 'em day and night. Charge your NIMH batteries while at work. Tactical flashlight in front, Radbot or PB Superflash in back. Think about a Kona Africa or KHS Green, maybe a Torker T-300, zip-tie a dairy crate to the rack, get some tire liners, a mirror and some pepper spray and you're good to go. New chain every six months or so. $500 max.