I made a decision to go for the OpenCockpits interface boards.
I will start with IOCard Master64, which provides 72 input and 64 output signals and USB Expansion card, which enables the connection of four master cards and everything together to the PC via USB.
Boards can be managed and programmed with the help of three programs that are quite user friendly, at least it seems so. I’ll have to learn some spanish!
In two hours “trial and error”, I connected strobe, beacon and taxi light switches together with landing gear lever and some light signals. It feels good when you can flip a switch instead of keyboard key and strobe lights turn on. The next challenge are rotary encoders for radio and autopilot.