Game bugged on one of my failed attempts and round counter kept going up and up, went beyond 3000 rounds and many thousands of gold/currency before I closed it. Then I got sad because I had to close the game and lose my progress :D (
Fun game although a tiny bit confusing at times, like I had to play a while to get a feel for what the different towers and different staves would do as a powerup. Didn't figure out what all the other weapons did except the axe. Other confusing moments was the pause button as others have mentioned, and the selection/deselection mechanic. Discovered the main feature of dice rolling towers a little too late.
I thought the colored "towers" had different abilities at first, such as blue = slow, green = aoe and such, but I assume they are just different stats version of the same tower.
I was building an idea that the strongest possible upgrade for a tower was to make a red tower with red staff for max damage, then upgrade it max with speed since each 0.1 second would weigh the heaviest vs ~0.15 damage. Or in reverse; the fastest blue tower with the blue (or yellow staff) with max damage upgrades would make the machine gun effect hit the hardest. Red with axe was a fun shotgun up close effect.
Your game has lots of potential! Keep it up :)
A possible direction to take the game is to go into the main mechanic more, mainly the dice roll. For a chancy game, I'd think if you could balance the income with a no-upgrade-limit, it would make a stronger dicey experience. With increasing cost it will balance itself out, and getting better dice rolls through upgrades between games might give it a sense of progression that carries on between games, like a rogue-lite would make you a little stronger game for game (like Dead Cells). Something like Warcraft 3's custom game Poker TD comes to mind. Luck is a major factor but your knowledge of the game matters as well