one list I like is "recent games" which I usually select based on whats added in the last few releases of Mame
That could certainly be done. I would need another data file to know that information though. MAME's -listxml output doesn't tell you what version a particular game was added to the list. If there's a file like that (I assume something like catver.ini) that you could point me to, I'd be happy to add that support.
The other list I like is "4 player games". I would love to see version added support and number of player support in romlist 
You can dig those up now. Just edit the -find text window, and add:
& numplayers=4
to the end of the of the text.
This information comes from controls.dat though, which is approximately 50% behind in the number of games mame supports, so you won't find all of them.