Yeah,the new kid in the block is bcachefs and i've been testing it a few months. Has some really neat features, but similar to zfs it is not in the kernel.
This is not a big cluster,but i usually recommend to my clients to split clusters into something like 15-20 nodes if they are unsure about stability of it.
You now how PDM, live migration works good.
7.0 is a test kernel,not an enterprise kernel atm, so if you are okay with breakages you use this kernel. If not, you usually pay for enterprise subscription.
Why would you be angry on a company giving you a test repo?
Did you try 7.0 kernel?
sudo modprobe tcp_bbr
sysctl net.ipv4.tcp_congestion_control
On 7.0 i get:
net.ipv4.tcp_available_congestion_control = reno cubic bbr