I do wish there was a good way to allow playing multiple cards at once, but I haven't found a way that works super well. If you have any ideas, I am interested!
I have no idea how the code works, nor how to program, just to preface. why can't you just remove the value pinging, just let the math update without the pause and locking in? maybe you'd have to remove that number pinging flair, as it currently is but the gamefeel of playing the cards smoothly is preferrable imo. maybe you could have the pinging animation not be tied to a delay and continue to happen in the background or have a separate counter panel to the side that displays some animation instead of on the actual card - maybe that would be easier to work in? the 3x sped up animation option is already getting to that smoothness save that lock-in. maybe you could just speed up that ping flair more, so it would be near instant?
or maybe when you click a card while another card's animation is playing it could spend the energy in advance and queue up that action to play the card as the animation ends instead of having to wait for the lock to end - that would make the card selection/playing feel smoother, watching the pinging aside.