LiChess analysis is free and better. I don't know what the Chess.com paid analysis is like, but on LiChess you can just run Stockfish on your games and analyze different lines as you like. On Chess.com you have way less flexibility (at least with the free option).
I'm still not convinced by PoS, but at first glance, since money = work then PoS might be viable, because what's the difference? Energy goes into creating proof of stake coins, just like it goes into producing proof of work coins, so they should be equally viable... that's what I thought the first time I seriously looked at PoS.
I want to believe that PoS is not simply an attempt to get something for nothing, but I think that maybe it's attempt to get money to work twice. In PoW, the work is done to get coins. In PoS, the work is done to get fiat or whatever, then exchanged for PoS, and then put to work mining, but the value was created outside the PoS system and now it's not clear where additional work is taking place to fuel block validation. I haven't decided 100% that it's a scam, but it is definitely complex and confusing.
The mental model that I'm still stuck with is that PoW is like normal combustion engine... ASICs being high-displacement V8s, while PoS is like some kind of complex perpetual motion machine.