Thanks for the advice, and for everyone telling me to not worry about it. Since I have no interest in racing I won't be tempted towards lightweight components, so it sounds like I should be okay. Are there any types of wheels that are particularly sturdier than others?

I still honestly haven't wrapped my head around the idea of buying a bike. Over the last few years I've been finding bikes in dumpsters, fixing them up, riding them for a few months, then selling them when I find a better one. I've had 3 beater mountain bikes that I've ridden a fair bit, and 3 10-speeds from the 80s which I couldn't ride because the frames weren't even close to the right size. I'm finally starting to admit that getting the bike I want will involve shopping, and that's just something I'm not used to. I've managed to avoid a lot of decisions by riding literally whatever I found.