The original intention was to have each door that you were able to open be locked, and you had to retrieve the key by defeating foes, which would ideally help you level up in each area, especially since you get a full heal when you level! That would have gated the hardest area (forest) from being accessed too early. But I definitely agree the respawn rate ended up being too high. 20 turns sounds like a lot, but it's really not!
Thank you for playing and the feedback!