After I always excuse myself having no time, I wanted at least to update this thread.
Meanwhile we finished and tested v2 of the controller board. Some bugs have been fixed and we have added some features.
The diversity controller now talks Jeti, S-Bus, SUMD, Mlink, DSM2 and DSMX and converts the protocol to S-Bus. We removed the auto detection since I found out that if both signals are lost, the controller needs to much time to find the right protocol again. Now the receiver type has to be selected via button once. Both receiver connectors have a JST EH 4-pin connector providing 3V3 and 5V.
We have added LED drivers for a 3W external LED which is dimmable via radio channel 8. The output is a combination of the AQ status LED 1 and our health status and has been kept very simple: a solid signal means no GPS lock, a double flash means GPS lock. Green = no error, yellow = non critical error, red = critical error. Both error conditions will be forwarded to the AQ6 by reduced power (fail safe). A small onboard LED helps to check the status on the ground.
UART 1 can be switched between a JST EH connector with switchable VCC and a XBee socket. Though there is probably not much use anymore for a power supply for servo gimbals, we left the 6V 5A recom because it provides a nice solid voltage for brushless gimbals.
All other functions such as monitoring of ESC status, power consumption, rx signal strength, battery conditions and so on remain the same. Though I'm quite happy now that everything works perfect, we already design v3 with FCU redundancy to match the Austrian law.