Thanks for the input! :)
After long consideration I have decided to go for the following scheme (mostly because I am still reluctant to use 2NT as transfer after 1♣ opening; as I just don't see how it can work with constructive hands with clubs that lack a stopper ...
Perhaps you could convince me further. I did consider it but the 2NT transfer to ♣ feels a bit problematic here.
In 1NT auctions the NT has already been bid by the opener and usually he is the one with stopper(s), thus the correct hand is playing.
Here, though ...