I've never seen much in the way of individual games on P2P only sets. Obvisouly I won't play everything, I tend to skim through the list and find stuff by companies I like or anything recent then give it a go and make a mental note if its worth coming back to.
The full set of ROMS plus all the chd's is a whopping 21.5GB though its 'only' 2702 actual games as most are regional variations or revisions.