One big problem that definetely will come up with a vote-kick system (as it has come up in any other game that features votekicks) is that people will be exploiting the feature whenever they can.
The issue is that many people don't really look for a reason when a votekick is started, they simply press the Yes-button to get that popup-message from their screen, and then it's done for them. Actually asking for a reason and evaluating if said reason is a) true and makes a votekick reasonable is something most players won't care about. As the game grows, more players will come, and the more players, the more idiots/trolls are playing. On top of that, a newbie will have to deal with many other things and probably won't watch the chat/battlefield too carefully. That has been an issue in games like WoW (dungeon groups) or War of the Roses/Vikings, where some people just love to abuse the votekick system, simply because they don't like a player.
Of course, that does not mean that there is no reason why you would want a votekick-system, but in my opinion and experience from other games the disadvantages outweigh the advantages by far, which is unfortunate but something everyone had to deal with.
I actually like the idea of an autokick though, of course its' parameters would have to be tolerant enough to not kick players for mistakes/misjudgements, and should give them a warning first. However, I'm not sure whether or not the effort would really be worthwhile, as the game will be open world anyway, and the current sea trials are just a testing ground for the combat.