If you're building an AES collection specifically to
play those games rather than just have expensive paper weights to sit on your shelf for an eternity, just focus on the games you know you will play before anything else. When I began my current archive I made a list of the games I knew I wanted above all else, focused on those first, then went for some additional filler. At 67 AES games, I've reached my max and have an archive of awesome games I can pluck off the shelf at any time and enjoy.
The worst thing about the AES market is the skyrocketing prices and missing out on a "good deal." If you buy a lot of filler just to have more games, you'll likely sell those games off, often at a loss, to be able to afford the "good deal" on the next game on your must have list.
All that said, you do you, man.