So far I find the difficulty fine and that is coming from soneone who never beat the game. I think there should at least be some challenge for the player, he shouldn't be able to run through his first attempt. Five/seven floors aren't even that long. If I compare it to Isaac, it has a similiar feeling in difficulty: Isaac is way too hard for me, when i first beat the mother I was glad to finish the game for the first time. It took a lot of runs to manage that, a lot of trial and error and in the end I did it. The same is with Starward Rogue, I want to learn from every death and push forward, eventually beating the game, also if the game would be manageable with single attempts, there would be no need for the AP system.
Just a quick question: I don't get what health shards actually do.