Would love whenever possible.
The instruments would have individual notes you could play like the guitar in S.T.A.L.K.E.R 2. Also would be cool if you could record your music on a vinyl (something more in line with lore haha) and play it in your home.
For the mini game, perhaps something like ‘Dittle’ a dice battle game. Of course a variety of games would be cool, a card game, buy different cards from vendors like how Gwent was. Being able to gamble, not just money but weapons/armour/items I think would be fun.
Would be amazing to see one day! Love the game, its amazing!