Building a Library?

I recently posted here about my sprawling collection of seldom-listened-to Tchaikovsky and got some excellent suggestions about what might be the 'core' Tchaikovsky repertoire, and what might be the most recommended performances of said repertoire. A pile of dross hit the bin in response, and I feel I've got a worthwhile, discoverable collection to work on going forward.

I wonder if I've missed similar threads about other composers? And if I haven't, whether it might not be a bad idea to put some together?

I notice my Mendelssohn, Beethoven and Schubert collections, for example, are similarly sprawling, 'completist' and thus seldom listened to. If, instead of having everything those three wrote (from one Brilliant boxed set or another, which seldom contain the absolute finest recordings of anything), I could whittle things down to the must-haves performed by the must-listens, I think that would be progress!

That's conceptually different from the posts we often see about 'what's the best recording of X?' or from the 'lists of top composers' or 'lists of top pieces' we also see. This is more: here's a composer, here is his/her greatest works, and here are a few suggestions for great recordings of each.

Anyway. Just thought I'd throw it out there!