I see myself ratcheting down to the core of what I really love. After 7 years of collecting, now, I'm already moving towards that goal. Similarly, I've collected modern first edition books for the better part of 17 years, and I presently have about 50 or so in my collection, down from about 2000 at its peak. But I'll tell you this -- when I look at those shelves, the books that have made it to that final 50 really say something about me as a collector, and I think that's the whole point.
I only know at this point that my two really-loved areas of collecting are clearly Japanese and Advertising posters. There's a few in other categories that are keepers, but buy and large I've begun to focus on those two areas. Even so, believe it or not, I think I will end up collecting only advertising posters, keeping only a few handfuls of the Japanese material that I really love. And, believe it or not, most if not all of that Japanese material would be that from the 70s and earlier, like the two-panel I have for The Diary of Anne Frank.
The joy is truly in the journey, though, and I'm glad that I can enjoy that journey taking some experience from the first round I went through with the first edition books.