Author here - the project did originally just have fault and latency modes, and the last one came out of discussions with a colleague about other failures that might be interesting.
I'm looking for more failure modes to add, so if you can think of any more send them my way!
Unclean network disconnects. We had to dynamically change iptables to simulate that particular failure case. It's hard to repro but something that does happen in prod and something that can cause mem leaks
Pausing within a synchronized block to exaggerate slowdown sounds really interesting - and would provide a great opportunity to learn about how locking works "under the hood" :)
I'm looking for more failure modes to add, so if you can think of any more send them my way!