I’ve played the GOG version on Deck but if anything Steam version probably runs even better. Text and UI size was sufficiently large - I would maybe want to increase the text size by another 10%.

It has really good in game controller support with all sorts of hints on the UI. The movement is done using a joystick IIRC. I don’t remember using trackpad or joystick as a mouse much, but maybe for some object interaction?

All in all I’ve played through the whole game on Deck and highly recommend it.

Another one here! Mostly playing Witcher 3 at the moment. And before that Disco Elysium.