true, I think a better thread title that conveys what the OP was saying was "most complete collection". That still is subjective but not as subjective.
I think the most disciplined collectors will pick one or a few very specific things to have a laser focus on such that they get really deep into something rather than sort of knowledgeable about many things. There are enough records in almost any subgenre of R&B that you can collect pretty much forever. If you just randomly buy all types of records you usually end up relying on other people to tell you what to buy and put on your want list. When people ask me why I don't buy doowop, gospel, etc. I tell them that I like a lot of different kinds of music but am perfectly happy to listen to mp3s of that music -- for me collecting is a different act than just "buying music you like".