The working of cryptocurrency is flawless, but the current mechanism or the way it works has some flaws in my opinion. Like the Nakamoto consensus mechanism, how the actual code runs, who has and does not have the right to modify the code, does the code after being deployed on the mainnet needs to be modified in the first place, does the code needs to be fixed-static-immutable, governance (51% limit), POW vs POS vs different types of POS etc.

I will write it in detail on my blog and post it. The basic theory is in my head, I just need to write it down properly.