Statistics and hints
If you have to plan your own controlpanel and don't wanna overcrowd your
panel, this tool made by Robert Palmqvist from Sweden is a must. Find his homepage here!
Simply click on the screenshot above, and you'll redirected to
the homepage where I found it. It's all there in the download-section.
With this little tool, you can sort out which games need how many buttons, a 4way-stick, trackball, and many many more! Very nice!
Interesting, isn't it? With only two buttons you cover 66 percent, three buttons cover 83 percent of all games, adding a fourth even brings you to 94 %! Some games are even listed with 4 buttons and do need one either, e.g. Puzzle Bobble. Maybe this is with all NeoGeo-games for they had 4 buttons anyway, wether they need them or not, so actually two-three buttons might even cover more. On some other games the report is not right, too, but at least you get a direction of what is needed and what not.
As stated before, it's all a matter of your own wishes. If you like it to have all controls ever needed on one big controlpanel, just do it, and you probable won't have any stress with any game you want to play. If you wanna regain childhood memories like me maybe you should think about making less controls per panel, depending on which games do you like. For me, I'm mostly interested in the good ol' 80s games like Donkey Kong, Centipede, Phoenix, PacMan, which might look more realistic without having fourteen pushbuttons on your panel! I guess I'll try out one panel that can play (well, mostly) all, and some for the feel with two or three buttons.
The maximum I found for trackball games is four buttons for "Disc of Tron". If you wouldn't need this game, three would be enough, as used on Missile Command. I'll go with three on my trackball-panel, so this is the first one in "classic" style.
I also will make one panel with only one joystick in the middle for all the "alternating" games that had only one joystick dedicated - it's very disturbing to have two joysticks on these games and to have only the possibility to use the first one or both at the same time. Plus, the current player stands always in the middle of the monitor, which is much more fun when you are playing solo. Mostly all alternating games don't need more then two buttons.