this would effectively be a compressed database. I like this idea a lot. I kinda want to try it... but the database would be completely different.

but tbh, most the storage space seems to be from keys and signatures anyways. i guess you can have a dictionary over pubkeys, but .... eh 

 Yeah, the dictionary of keys and IDs was the first thing I did on Amethyst. It's why our memory use is minimal. There are no duplicated bytearrays anywhere in memory.