You can't punish people before you get the MM right.
'Ghostattacks' (attacks that hit you even if you blocked them successfully) are pretty common 'cause p2p sucks. I can't blame leavers if they leave for understandable reasons.
Wait for dedicated servers or quit playing against players as long as those problems aren't addressed and fixed.
Here, I made a post on Peer-to-Peer connection: http://forums.ubi.com/showthread.php...play-For-Honor
There's a petition inside. I know it won't probably do anything but just in case.
The more people we can get, the more our chances to have Dedicated servers is increased.