Firstly, the music is fantastic, and honestly a big reason I played it as long, due to it being so relaxing. On the note of issues, I agree with the previous player. If the music is what kept me zoned in and enjoying the relaxing progression, Shadow Step would be the opposite, breaking me out of that relaxed zone and quite honestly ruining the experience.
Each new Delve reached slightly deeper and brought slightly more gold, but unlocking Shadow Step suddenly took my party's efficiency backward, causing future runs to yield far less. As it stands now, the Thief gets soloed out and surrounded, thus the entire party takes damage on his behalf while trying to catch up to his position.
That said, I did truly enjoy the game. The music and art is pleasant, and the upgrade tree (although a little confusing) is nice being so expansive. As for the thief, might I suggest a temporary "invisibility" during that skill? At least long enough for the party to catch up? In any case, good game, good job.
Hoping the best for this project moving forward. ๐