Admittedly, You are totally right in regards to finding case sizes bigger than 38mm but it's doable but probably not so much in a classic looking dress watch.
And yes, part of having an interest in nice watches is also finding a good inexpensive local trust worthy watch repairman but it's the same thing when you buy nice dress shoe's or a suit.
I think the difference is taking the time to finding this knowledge and support system otherwise I guess the default is a buying a new Omega, Seiko or Hamilton...etc. I find it interesting on style forum with (some) members talking about getting $600-1000 shoes, $5000 suits and have found a good shoe repair and a good tailor for them but then they get a new Hamilton.
That's why I think it's a great idea what Hayward suggested, coming up with a abc cheat sheet for someone new wanting to buy a nice watch, new or old.
I'm lucky I have a guy down the street who will do a total service/restore/overhaul for a old non working watch for $150 or less making it look & run as good as new and then I have a really good watchmaker to service/overhaul my expensive watches but he's twice as much and then some but he's totally worth it.
I think this a great and needed thread (poor man's watch) because it's easy to spend $10,000 for a unique worthwhile watch but under $500 it takes much more creativity and knowhow to finding something you'll be proud of.
ok, I'll get off my soap box.