Thanks again for the suggestions. Being the OCD person that I am, I spent the time this weekend to go through the entire list of working Mame roms (all 7600 of them) - several times actually as I forgot to do some things the first time around - so hoping my work might pay off for some others looking for this same information.
After I got over just how many versions of mahjong, tetris, japanese baseball games, and even volleyball games that there actually are, I compiled what I think is a thorough list of decent clones. As nitz said previously, these are clones where the clone is the original game (Puckman/Pacman), the clone has extra features or levels like speedup or control hacks, 2p vs 4p, etc., the clone is playable and the parent is not, or the clone is actually a different game altogether that relies on the parent roms.
37 clones in all, whether you want to include them or not is up to you, I added the information you need to decide like game, parent/clone name, and notes. For me, I plan on excluding all clones on my menu but adding in maybe 20 of these for various reasons, will really simplify my selection menu.
Enjoy!
Scott