So you face the usual conundrum. I want to play all the games in Mame but how do you fit all the controls on the panel? I mean there is 4 way joys, 8 way joys, diagonal joys, analog joys, trigger finger joys (various types), track balls, spinners, flight yokes, racing wheels (various types), rotary joys, etc. Of course you can combine several of these. For example there are analog joys that support 4 way, 8 way, 32 way, and analog operation.
You really need to decide what games you want to play and support them within reason. Personally, I'm going with multiple cabinets to limit the controls per panel to look more like traditional arcade machines and allow play without getting into weird contortions or having my arms get tired because I'm trying to use a joy that is three levels deep.
You get the picture from looking at some of the previous links to frankenpanels.