There really is no solid estimate, it all depends on the player/latency/skill. You have lots of utility on LK, a good hunter knows how to maximize the little things, in order to improve despite a poor fight for hunters. Learn to stutterstep, as well as moving during instants. One of the biggest things to improve DPS, is simply to move less/more efficiently. Bear in mind, that if you are on orb duty, the chart is rigged against you to begin with.
good advice LISTEN TO IT - I top LK 25man DPS with around 12k, you could go there too, just adapt, use the right pots and remember to play your best.