20 is a lot, I don't disagree, but the number of levels was determined by the needs of the story, even if that story is strictly optional it was a framing device I didn't want to leave behind. When the mechanics were designed and implemented I wasn't sure how long the story would be and I only thought of potential level diversifies after the fact.
I do agree that the resolution is too low and the visual clarity suffers for it in multiple ways, it's one of the first things I would have done differently on a do over, proud as I am of the 16px lilies.