I use a manual switcher with my A4000 to toggle between the ScanMagic SD/FF display and the Cybervision 643D Workbench. The problem with an automatic switcher is how would it know if I want to see the native SysInfo display or my RTG IBrowse screen? If you need to toggle it via the keyboard then there's no difference between that and reaching out to twist a dial instead.
Yes.
But if you not use two display at one time, may be its possible to detect, when AGA active or not, and switch only if active...
Anyway I prefed manual too.
But at this time i use big and not very comfortable external switcher. (And 4 port kvm, to switch between my 3 pc and 3 amiga, and external tv-tuner for old consoles)
((