These are some great ideas, especially the simple ones like bringing a garbage bag. That’s something so easy and cheap that it’s easy to forget entirely, but as you say, it can make a huge difference in the right circumstances. It’s also good that you discuss some minor bike repairs. That’s another thing that can salvage or destroy your ride. You want to be as prepared as possible for the best possible experience.
A multitool is a highly versatile piece of repair equipment that can address most of your maintenance needs. Ideally, you should use it before a ride to tighten and adjust everything properly, but sometimes it’s necessary on a ride as well. If you encounter a loose screw, realize your saddle height is not right, or that your brakes need tightening, you will be happy to have it.
Our favorite hand pump for commuters is the Lezyne Sport Drive HP, and you can read more specifics about why in our full-length guide, written by Dave Yasuda, a writer and tester with over 30 years in the saddle. To sum it up, Lezyne makes pumps with an extendable rubber tube that connects to your tire valve, and that’s the difference between awkward and demoralizing. It’s not the only company that does so, but it is one of the few, and it does it the best. The Sport Drive HP can adapt to any tire valve, has no small fussy parts to lose, and inflates more easily to higher psi levels than anything we tested without floor leverage.
Modern bottom brackets use a sealed bearing type construction that keeps water and debris locked out, so they seldom go wrong. Maintenance is impossible so they need replacing when they do wear out. Older style cup bottom brackets need to be re-greased every now and again, and occasionally will need to have their bearings replaced. There are a lot more teeth on the chainring cogs than those on the rear cassette, so need changing less regularly. Cranks usually a solid one piece construction so there is not much to go wrong.