PoS can not be decentralized and can not be secure. You will never know if an opponent has taken control of all or part of the nodes, all nodes can be compromised or hacked.
There will be no greater security than just the PoW, there will actually be less.
I believe its easier
to hack 2 or 3 pools in order to control a network over PoW (and often 1 pool has more than 50% of it, so a single target to hit) than hacking all the nodes of a network. Pools also run more code than a node so attack surface is greater.
Network can not be controlled "over PoW" by hacking pools, because hashing power is in hands of miners not pools itself. I don't know how a PoS network can be secure and how a PoS based coin can guarantee privacy, because PoS is inherently centralized.
Maybe privacy is not intended for zano?
Not sure how much you have mined, but miners provide power to pools, pool is running the node so it can double spend and do all kind of things with that node, as long as the pow algo is the same miners don't know much about what they really do...
No surprised that everyone is worried about pools that owners near large chunk of bitcoin network...