All the newer alpha2 games require the iDeck. There are just a few that don't. Rule of thumb, if it works on alpha1 even if it is an alpha 2 type title (the cf card software ID has a number in the 3xxxxx range), then it will work with a standard button panel. All the newer titles, like Michael Jackson, Lucky Tree, Grease, Skeeball, etc require the iDeck. If you have a V32 you are trying to revive, Sea Goddess is a game that works with the standard button panel. Playboy Hotzone is a v22/22 title that also works with standard button deck.
As far as the power connector is concerned, I don't have the pinout for the alpha 2 pro backplane (I'm assuming you have that one since you mention the missing power backplane missing).