I can make some, when time permits me, hopefuly early next year.
I think the biggest problem to consider is that people having very different setups. Some of their Amigas have standard mouse others use ps2 or usb. Some need vga output others have scandoublers with dvi/hdmi. All those could not be mixed together with a dataswitch solution.
What it does, is that it switches between standard Amiga mice (db9), Joystick (db9) and Amiga type keyboard. In addition I recommend active VGA autoswitch (preferably with audio integrated) that will cover all the needs.
I just need a rgb switch to connect 1 screen type 1084 to several amigas. very simple
Mice can go to rs232 switch I think, as Vampire also has db9 mouse. I also hope joysticks can go to another rs232 switch. X68000 also has db9 joystick, although slightly differently wired. But the switch will just connect the wires right?