13 converter switch, what to inculde

[zrrion]

I have recently purchased an old KVM switch that looks like it was intended to connect up to 13 towers to a single keyboard/serial device/monitor. It does not include any circuitry inside that prevents making it work in reverse though, and that presents me with an interesting project, as I could design daughter boards for this that each house a converter.
Problem is, I am not entirely sure what converters I could actually fill the thing with.


The LED indicators are a big part of why I got this, the dial on the other old kvm I was messing with just didn't feel right and the construction was not very good. This switch (apart from having a lot more selections) is much better built with 2.1mm thick plate and connectors instead of point-to-point.



So I can see including a something for AT, XT, PS/2, WYSE, ADB, and USB pass-through but I am not sure what to do with the rest of the remaining slots. For instance, duplicate converters for XT/AT/Enhanced layouts that all use the AT plug would be convenient, but not worth it unless I really don't have other converters to include.

Any ideas on what else I could put in here?