OP, I fully understand where you're coming from, what with bitcoin being extremely environmentally wasteful, but that may be necessary to give it a base value, if nothing else. You need something like a production cost assigned to it, so there can be a reference to its fundamental value. With PoW mining , while primitive, it at least has a direct way to assign a production cost to it: electricity.

But however better cryptocurrency can be improved, it's not that there aren't alt coins that have better solutions and better technology than bitcoin, yet they still don't and can't overtake much less replace bitcoin. There's also the adoption and infrastructure, which is what really gives bitcoin its value. Bitcoin's first mover advantage really can't be simply overlooked or dismissed. The solution is not to create another alternate coin, but to just fully concentrate on Bitcoin and how to evolve it to be something better.