Thanks for playing and the kind words.
A few things definitely took a hit just due to time constraints, like you mention a lot UI elements and the title screen were rushed without being complete, I pretty much submitted this half an hour before the deadline. Also never having time to implement a tutorial, to the point I had to make one outside of the Jam time by putting the details on the game page.
If you want some technical details, each full rotation of the wheel is 1 point of damage. Getting Colour advantage gives you 2x damage and halves the damage you take, same works in reverse and matching colours are no change.
The icons on the spinners are Links, I'm not sure if you made it to a shop but you can also buy some for your own spinner. They are abilities that enhance your attack if the spinner lands on that colour slot and triggers the link. (Each slot starts at a 5% chance to activate but you can spend gold you get from enemies at the shop to increase those odds. The slot will flash white in a fight to indicate it has been activated)
The sword in particular is a very basic attack up which boosts your damage a further by 1.5x. But there are more in the game that are a bit more interesting.
I would have loved to have done a detailed explanation in game but it is what it is.