Probably a dead end.
I used to map, but I’m getting away from the workflow and going with smarter instruments (like Infinite Brass) that don’t use Keyswitches at all. Steinberg introduced maps 10 years ago in Cubase 5.1, but have had bigger fish to fry since then and still do. Unfortunately, mapping won’t get any easier and other developers aren’t supporting the framework Steinberg setup (automapping, expression, etc). Multiple MIDI channels and smarter instruments get 10,000,000x more attention. So if you’re looking for an improvement, I’d look there.
It’s worth mentioning that workflow things like this are why I switched to Studio One in v3.5. I switched back to Cubase in 9.5, and now I use both DAWs (and their notation counterparts) for different things. They all have good features, but also shortcomings. More and more, I’m leaning away from Steinberg though, and for reasons like this. I’m not ranting, just saying this was already long overdue when I requested it 2 years ago. Maps are one of Cubase’s biggest selling points. It just boggles my mind that they don’t seem to realize it.