Hey there! I tried Kord and I have some notes from my playthrough:
Something I noticed is that in the very first mission you already have to do a lot, including having to juggle more than 3 instrument types. The slot number system was confusing at first and it feels like there's all these small rules and limitations that create a stack of things I can't do. Kord is not as intuitive as I was expecting but I think adjustments could make this work.
I'm thinking it may be better to let the player do a few things before showing the objective and resance points, it felt like I was getting a bit overwhelmed at that point, like I don't think I even got to move any cards around and then I'm shown I can upgrade. I prefer having some context of what I'm doing before things that are congruent to that context are shown to me rather than being something I'd only understand AFTER everything is all laid out to me.
Gameplay feels like there should be this fun flow of switching cards around and slowly figuring out where everything will go, but each time I try a playthrough, I place a few cards down, and before I realize it I have all three modules set as different instruments, but my hand has multiple cards that can't go onto any of the modules because they're the wrong instrument and I dunno what to do with them, I can't draw too many more cards or I left a useful card below one that is the right suit but i can't do anything with it.
Maybe if you could stack 2 of the same card type (same instrument + suit) onto a module slot that could help alevate the restrictiveness, maybe it could power up that slot?. I couldn't get creative at all each time I tried to beat the first mission, and like others have said I just run out of slots/possible moves and get stuck.
If you attempt to beat the mission again after running out of time with the tutorial, when it tells you to buy an upgrade I think it's technically already upgraded and you can get stuck unless you press Esc (i think).
I'd see if limiting the amount of instruments and increasing the default hand size (5, maybe even 6) would help.
There's a cool game buried underneath the stacks of rules and restrictions but it's not coming through at the moment. I do look forward to seeing how Kord evolves!