Voted you up. I think if people looked into how Cardano does what they do, they'd realize it "cures" all of the ills of Bitcoin, Ethereum and every other unscalable PoW currency in an elegant, provably correct way. I personally think the future of cryptocurrency is going to look far more like Cardano than Bitcoin. Not saying any of the top contenders are going away, they just will be glued/superseded by something like Cardano for more or less anything these others aspired to become, e.g. microtransactions, better/nearly infinite scalability, etc.
PoW is not ecologically friendly, and that will be one of its growth inhibitors.
I have, but early on and not much since. I forget my particular issues; I just remember at the time there didn't seem to be a way to do what I wanted (I think it was adding docker as a dependency).
[1] https://github.com/Emurgo/age-usd