> cannot start a paxos instance for a new log entry until all prior instances have been resolved

It's wrong. In Grydka (Single-decree Paxos) all the keys are independent so it's possible to update them at the same time without blocking.

Grydka's throughput is comparable to Etcd on the same type of machines (4720 vs 5227 rps) and I never optimized for it (my goal was to fit 500 lines) so it's also wrong that it's "non-trivial to achieve the same level of throughput" - I did it by accident.

So I don't understand why Raft is a better base to build a fast high-throughput consensus protocol.