Knarr/Snekkja speed are extremely important in PVP because if you are faster you can either completely escape a fight or completely dunk the people in the slower boats. With the way PVP works in this game there isn't any place for variable speeds, the speed of people in combat should be the same always. This affects noobs a shit ton because a big chonker boi is almost certainly going to have a higher q boat which will result in them getting dunked.
In general knarrs/snekkjas shouldn't be involved in PVP at all as they're basically a mobile safe pali and they're great at blocking people in the water forcing their death. In my opinion the only use for knarrs/snekkjas should be hunting or traveling quickly through the ocean. They should have their speeds set to the maximum while in oceans and while in freshwater it should be the same speed as a rowboat so they're not used as much to block people in rivers and such.
Quality could instead affect either the cargo/inventory size of the knarr/snekk or reduce the damage taken while traveling through the deep ocean. I'm open to other ideas regarding this, however, it definitely should not affect speed in any way.
Also ideally people wouldn't be able to enter a knarr/snekk while in aggro, however, this would make entering someone elses snek/knarr who you're in aggro with impossible so there should be a work around if the person you're pursuing is currently in a snekk/knarr.