Having finally got my account transferred and tested the waters on PC, I was able to try the game with a controller again (over USB for now), and it's awesome! I actually thought I had to do some special setups etc, but it seems to just work plug'n'play.
The feeling of playing with a controller is great. It feels like less of a transition, although the audio output on the controller is not working (but I'll probably find a solution). The only interface issue is that the shop is not working, it's not really possible to go to the shop with the controller.
Well well, anyways, I hope CDPR keeps the controller support now that the console people are/have moving/moved to PC. If not, it would be nice if CDPR would support a project like DS4Windows so we at least can emulate a mouse and keyboard with a controller and use a controller in the game despite no real controller support. It seems like a pretty decent alternative, although not as good as "Qjoypad" for GNU/Linux.
But that's another topic, would be great if Gwent had a GNU/Linux port, but ok. Seems we're stuck taking it in the back from the likes of Google, Microsoft and Apple for now.