The problem is how do we define contribution? I would be in favour of scrapping votes completely, but they do serve some purposes, like sorting posts. We have tried to come up with ways of handling different post sorts and votes, but all of them have problems equal to or worse than the current system.
I looked at a lot of sites to see how they were doing it, and none of them have figured it out yet. we may be better off just fixing problems with it when they arise.
I like the role of votes in sorting posts.. on some websites the reverse sort is most useful. Again, I'm not suggesting getting rid of votes or replacing their function sorting posts and comments. I'm suggesting measuring contribution to the website in a better way, just in case you need to restrict user rights at some point in future.
Contribution should be defined according to what you want phucks to turn into. In the absence of a detailed explanation of what you want, I assume you'd like to steadily grow a varied community of individuals who enjoy communicating their interests and viewpoints while at least being tolerant of the views of others. The xyzw point system above is basically compatible with this. I think choosing to measure contribution based on popularity (as done on voat) is incompatible.
Fair enough concerning punishing lurkers.. I suppose a single upvote counts as some sort of contribution.
I know the XP system is currently quite innocent - but if you feel you need to start ranking/restricting users I assume that's what can and will be easily 'weaponised'.
With this in mind, do you think the XP score really measures what it should?
Edit: I'm not suggesting discarding XP altogether, something like that based on popularity is expected from a reddit-type site. A contribution-based score could be introduced in parallel.