+1 to this. I am on Assignment 3D (dealing with log compaction in Raft). I have learnt more about Distributed Systems just by "auditing" this course.

For Paxos, I also recommend reading Paxos v Raft, Have we reached consensus on distributed consensus ? by Heidi Howard et al. It explains Multi-paxos by using the style and abstractions from the Raft paper, which makes it much more understandable. Paxos can be intimidating but this was the paper that made it click for me.

I highly recommend doing the labs from 6.824.