First off, thanks for taking the time to give such a detailed comment.
I think the idea came to us as we had been watching a GDC talk about creativity in ideas by adding limitations and had been talking about how we could use dice and card draw mechanics in games.
As for your bug, it could have been one of two things and to help us test for it. Was the blue thing just bobbing up and down and shooting things at you? I suspect either you were stuck on the creature itself or the blue fire projectile. You should be able to move away from either but wonder if you got weirdly stuck on a collider or something.
As for post-jam, we have plans for the game. We aim to add a player class system that has a card draw mechanic for special abilities for use within runs. We want people to be able to upgrade their classes and general stats to be able to feel progression. This might be through equipment or some other system. I have wanted to add pickups of some kind that allow you to re-roll or provide a one-time modifier but we are still planning these aspects. I do like the idea of having something that can only be done with low rolls to feel less bad when those double 1 appear.
Thanks for the feedback on the UI, I do plan to add some animation or identifier to the dice in the dice pool to make it obvious that they are your active dice. At this stage we don't see adding any more dice, however, will consider your suggestions on the layout.