FAST's idea sounds better. To document known compression schemes on games.
But having a list of NES games which are compressed to
not wasting time on starting projects on compressed games
to check if the graphics are compressed is like a couple minutes spent opening the prospect game in a tile editor.
If you know how to build tables easily, then finding if an NES game uses compressed text is like 10 minutes. (most often the table can be found by looking at the PPU Viewer in FCEUX, to find the tile numbers for characters in a test string. If that fails, fall back to the Relative Search method people used before.)
That's like 15 minutes spent researching potential games.
And rarely is NES text compressed because simple to decode things like dictionary.
To document simply compression or not seems like a lot of effort. And I'm concerned this sort of post (not to point at anyone in particular, I've seen several of them lately) is from people who may not be ready for the kind of patience needed to succeed in ROM hacking.
But maybe I'm just a cranky old guy in the scene.
When you make ROM hacks, it's practically guaranteed you're going to make mistakes that will leave you banging your head against the wall for hours, maybe days fixing them.
Not to mentioned deleting or losing files at some point or another that will force you to do stuff over again. I'm sure many of the best have done that once or more.