The game is fun! I find it's a bit too much self-service when it comes to difficulty. You can give yourself maximum bombs and then all levels become super easy. I feel level 20 should be challenging no matter what you tweak in the UI.
I see what you mean though I wanted it to be as accessible as possible while offering a good (or brutal!) challenge if you want it to. The easier the game the slower your score increases btw. So the score you could achieve by beating the same level will vary drastically depending on your settings.