I think you mean custom device drivers. A virtual device is just that, it exists only on the hub. It sounds like you have physical devices that might be able to work with HE with the use of custom code.
Ah, yes and no.. So all my devices (eventually) talk MQTT, which is picked up by my node-red, mapped to a Maker API call, and then I want to leave the rest up to Hubitat. So "virtual" device drivers , a subset of custom device drivers, that work nicely with the MakerAPI are what I 'm interested in.
I certainly don't want to firmware update the little buggers to get them working with HE. You never know my hub may yet end up sat with the ST I never gelled with - though that's really unlikely.
So far I've hacked together a couple of really simple virtual devices that manage some of the peculiarities of my system (e.g. report motion, but never report motion-ended), but finding decent templates is not a one-stop experience.
The idea behind a wiki would be to gather these together - a virtual device is NOT a real device.
I'll almost certainly be contributing to community wiki listed above, even though my experience with groovy and HE/ST development is yet to hit a week.