This is a very large can of worms. Neither the ATK or the Kingpin is release tested like an alpine binding. Marker has spent a fair amount of time and money trying to assure us that it's safer than other pin bindings. As far as I know there is little to no data to actually prove that one way or another.
Both the ATK and the Kingpin have two release screws in the heel, you can adjust both lateral and vertical release values on both bindings. I personally feel just as safe jumping off stuff on the ATK as I did on the Kingpin. Neither of them have adjustable toe release, so I don't trust either as much as I trust a Shift or even a Vipec to come off. This is the risk that comes with skiing pin bindings.
If you're getting a sub-1600g ski though, don't put a heavy binding on it regardless, that's just silly. FR 14 would be the biggest, heaviest binding I'd consider putting on a ski that light.
There are lots of skis that are easy to turn in tight terrain. Personally, for deep snow in tight trees I've enjoyed all of these skis: Moment Deathwish Tour, Moment Wildcat Tour, Atomic Bent Chetler 120, Line SFB, Line Vision 108. At the weight you are talking about, I haven't skied as many options, but I'd be looking at the Commencal Meta (even if it sucks it's cheap and light so it's a risk worth taking) or something from Moonlight Mountain Gear. Their skis are stupid light. Movement also makes some very light fun looking skis, but I haven't gotten to ski any of them.