I know this is an OEM Rextron USW-KM304, and I already emailed them asking for this feature, but I thought perhaps you, as an actual reseller would have more sway with them.
I love the KM, does almost everything I could ask from it. There is one feature that would put it over the top… “keep awake”.
Essentially, whenever the KM is actively receiving mouse or keyboard inputs it should (optionally) send periodic tiny mouse movements to all connected computers. This way, when you are at your desk furiously working on a project (gaming), the connected laptop where your email/slack/etc is displayed will not lock/sleep on you. Only when your actually away from your desk and there is no KM input, should it allow any of the connected computers to sleep.
This seems like it would be relatively simple to implement, assuming these have updatable firmware, and would make a multi computer setup even more productive.