|For your type of skiing, I'd recommend a narrow waisted ski, no more than 73mm under foot and mid-sixties is better, with a sidecut radius of 14 meters or less.
Skis of that description (basically ones derived from slalom race skis) will carve very tight turns, and hold extremely well on ice and hardpack. However, you might have issues with them in more variable snow conditions -- this is not as big a concern on the east coast, but it can happen a lot in the early or late season.
Something on the narrow side of the "all-mountain" category (in a 72-78mm width) would be somewhat more versatile. The Zeniths and Metrons you mentioned are both in this category. For K2, I'd look more at the Crossfire or Ranger, since they run a little narrower and would be better on harder surfaces. (They also have a new "Sidewinder" that is between the Crossfire and Recon.) You might also try something like a Head SuperShape Speed. That is more like a GS ski -- better at speed than if you're going slow, but will hold great on firm snow or ice. The upgraded Head Xenon 8.0 or 10.0 might also be a really fun ski -- the new ones are supposed to be stiffer than last year's models, which was my biggest complaint about them. Personally, I'm on Dynastar Contacts (the "Limited Edition" from last year, which is this year's Contact 10), which I like a lot.
Frankly, there are a lot of good skis out there. What it boils down to is finding one that works well for you. realskiers.com is well worth it if you want trustworthy descriptions of many different skis. However, demoing is still extremely helpful in figuring out what you like. If you can find an on-mountain (or near-mountain) shop with a bunch of skis you want to try, you can often test multiple pairs of skis in a day for the same price as demoing one pair.