Beat case scenario: your grave sits unlooked at 99.9% of the time and wastes space. In a couple hundred years some douchebag archeologist who wants to pretend they aren’t a grave robber will fuck with your shit in the name of “science”.
Setup a shrine for your loved ones in your house if you have to. The world is for the living. When I die toss me in the nearest dumpster.
Skip the cremation and just be buried and have a sapling planted in you. Trees love bodies, lots of nutrients.