Launchbox controller mapping with multiple devices

[imsoinzane]

Hi Everyone! So I am building a 2-player arcade cabinet and have a few questions before I purchase the hardware. So I will have multiple emulators installed such as MAME, N64, Dreamcast, Sega Genesis, NES, SNES, GameCube, PS1, etc. When I boot up my computer, I will have it automatically login and open big box. Then I want to be able to select the game with the joystick and buttons and start it using only the joystick and buttons. 
 

For MAME, I want to use the joystick and push buttons and already be mapped so it remembers the mappings for both players when I choose a MAME game. But for some systems, it is not practical to play with joystick and buttons so I will have a USB port with a wired Xbox One controller for playing systems like GameCube and PS1 and Dreamcast. Now that you know my setup, here are my questions...

 

1. Is it best to use an IPAC-2 for this or is it equally as good to use 2 zero-delay encoders?

 

2. What is the typical setup for an arcade cabinet joystick and controls? I.E. having 8 action buttons, joystick, player button, coin button, and select button for each player?

 

3. If for some reason I want to be able to use a joystick and buttons OR an Xbox One controller for say N64, do I have to remap it in the emulator to switch between controllers? And do both players have to use the same controller? Or can one use joystick and buttons and the other can use an Xbox One controller?

4. For each system, do I have to map the controls in the emulator itself? So if I have 20 systems, I have to go to each system to map the controls? I know RetroArch handles most systems but what if I use RetroArch for N64 and SNES but want to use an Xbox One Controller for all N64 games and want to use the joystick and buttons for all SNES games? How do I map the controls? In Launchbox or in each emulator?

 

5. If I’m using RocketLauncher, can I set up the mappings from there for each system? Or maybe use something like JoyToKey and apply the mapping differently through each system in RocketLauncher?

 

Sorry if these questions have been answered before but I keep finding very general tutorials and answers and I don’t feel like they fully answer all my questions.