We don't need mining in the first place never mind CPU-Wars and I would say that PoS is better than PoW but it does come with problem too
and I would use that word "Trust" that gets established but I am sure someone would come along and beat me up for swearing.
I mean one broadcast results in 20,000 nodes trying to agree on whats said and then putting a finger in the air to try and guess quite what the next block
will look like as they all try to stay in sync with each other.
it is not a brilliant system by any means, it's slow, it's costly to run and is 1st generation with none of the new coins taking
much from it at all and they can present a public ledger without budging it by going "off-block" and having a number of single points
of failure as is the case with Lightning banking hubs.
ETH with the concept of "Smart Contracts" brought more to Crypto-World than hashing data and linking it to the next
block in the chain in what is really just a read only supped up version of something called a linked list
What gets up my nose is they run out of resources and then up the transaction fees as if they didn't know from day one
that bitcoin would not scale so what we have today is nothing like the original vision of just being an experiment to play with
and coins not being worth a dime.