I'm just over 500 miles, never exceeded 350 pds, & cold can be a hassle. Get a ski mask & wear multiple layers + some
sort of eye protection, 'good gloves' a must. The high humidity here seems to treble the chill factor
A stick got flipped into my spokes, broke 2 & bent the derailleur a bit as well. I managed to repair the spokes without removing
the wheel. It's tricky; you can't just put the spoke thru the hole & thread it into the old nipple because the nipple
threads are stripped. What I did was to break the tire bead a lever, & pull the tire & tube out of the way. Here's where it gets tricky. You need
needlenose pliers to insert the new nipple into the hole. If you are not very careful, the nipple will fall inside of the hollow rim. Then
you'll have to jiggle the rim around to get it to drop out at the bottom. Once it's held in place you can thread it onto the spoke.*
As for gear, I ride all the time with panniers, an inframe, & a handlebar bag. I do 90% of my shopping on the bike.(see pic)
*Using the same technique,you can patch the tube without removing the wheel.