As a rougelike enthusiast, I can say that this is a crazy good game. It needs some balancing of relic stacking, as you can become unbeatable in just a few levels. I believe this is a very good idea for a game, and it can (and hopefully will) become successful.
One thing that could be added later on is a system or doing certain things that would unlock relics or consumables. I have not yet discovered all items, but adding items or relics that require you to modify the way you play (permanent 1 heart - one relic option with items each stage, or lose heart every 20 seconds - triple gold and take all items at end of stage). Adding certain concepts to each type of item - usually done with godly blessings, challenges, or tarot cards - will help flesh out certain item types or story.
This is a great concept, and I am looking forward to what you can do in the future. My quickest Steam wishlist of the year.