Raft essentially only allows a single mode. Moreover, you are starting to see people putting things on top of Raft instead of something like Paxos, in the enterprise, because they don't know any better nor have the foundation to understand what they are doing is "wrong."

> When I got students to implement MultiPaxos, I never could get sufficient confidence that it was done right

Testing this is fairly straightforward, they should be able to join an already existing cluster. If they got it wrong, it shouldn't take down the cluster, and they should be able to step through their own code. There aren't any timeouts, so they can take their time, going through each step of the process until a value is committed.

At that point, you simply explain each step as an individual algorithm, not the sum of its parts. You can even build each part individually because an existing cluster should recover from a misbehaving peer.

From there, it is a rather simple visualization process to see what is going on.

The hard part of paxos is building it from scratch.