For you, at your level and tier, they already kind of have an option for that:
If you bought bigger high level sticks and played the best of par 3, for all intents and purposes, it would be like a pitch and putt, off pro tees
or
you could play a nine hole CTTH of your choosing, then a 9 hole CTTH Best of Putting
Neither are exactly what your looking for, but close enough. Unfortunately I don't think you will get much support from the community on this, nor WGT. I think there are a lot of other things the community would rather see and a pile of stuff WGT need to sort out in the near future.