Here i am! Took me 6 runs.
I really like the key-lock style design of the level where you have to collect necessary abilities to pass obstacles that you could't pass before. And that fits really well with roguelike mechanic.
For the downside I can think of is the atmosphere. I think you can add some post processing (not sure what this called in godot, but generally sth like camera effects) to the scene with some lighting to create kind of dungeon feeling. Also I think the FOV can be shorten a little bit.
For the gameplay part, definitely look forward to see more creative design of the use of the shotgun jump(Ex. some moving spikes or spell balls that would require to shot jump to dodge etx.) And also some animation when you walk would be perfect.
Overall, I love the natural combination of lot of mechanics and I think it would have greate potential of becoming a addictive roguelike game.