Wow, thanks for this detailed feedback! The gameplay definitely needs some rebalancing, we didn't have that much time to adjust it, especially remaking the levels would have been very time consuming if we did it, and our priority was to add as many dice and enemies as we could in order to show the potential of the concept. The dice ammo system was intended to encourage you to go in and collect the dice dropped by enemies, though we will definitely have to make some changes to it. One thing is that respawning should refill your ammo, but we didn't think of adding that in time, it would have been an easy fix. One other commenter also suggested adding a dodgeroll, which makes it easier to escape the fast enemies and reposition and also allows you to collect the dice dropped by enemies without having to kill a whole group first or lead them away from the drops, I think the dodgeroll is a good idea. Your idea of manipulating the dice queue sounds good, we might implement something like that in the future, though I feel like it already kind of works because even if you are forced to use a certain die, you can choose which way to use it.
It's unfortunate that many players told us they didn't get how the bomb dice and heal dice work, because we actually explain it on our game page (https://miniver-games.itch.io/die-sorcerer). Unfortunately, there is no space for a description on the submission page and since it's a downloadable and not a play-in-browser game many players never looked at the game page. Obviously, we would have wanted to explain how the dice work in-game as well, but didn't have enough time. The bomb dice and heal dice are examples of dice that you generally want to avoid hitting enemies (directly) with, differentiating them from the speed and damage dice. The game page also contains a list of some known issues which we couldn't resolve in time. Another obvious issue is that we are missing sound effects, which we actually did make but we couldn't properly implement all of them in time so we decided to have none and just the music.