Neil,
June before last, 2 good friends joined me on this little jaunt up Esther. We were intrigued by Johnnycake's enticing route off the toll road a short way past the toll booth. He'd done the stream a number of times in winter and it looked inviting. Without 6' of snow, and staying out of the moss-slicked stream bed, it took 4 hours of slashing to top out on Esther's ENE ridge. The faint herd path to the summit from there felt like the Northway. There were pine needles jammed into parts of our bodies we never knew would accept them. The price I paid for my stubborness about putting on long pants, were scratches and deep scrapes that caused others to stare for 4 weeks afterward. John and I have spoken about the route afterward. Its very nice, but like some bushwacks, being 50 yards left or right can make the difference between easy and a deathmarch. I think the way to do this is in deep winter, lots of consolidated snow with a good crust and stroll over the unseen garbage below.
There is another route up Esther we've been eying for years. Out of the ASRC, you can see a long ridge that comes from the north and east. In winter, the upper portions look like lots of open area. With good snow, climbing that ridge is something that looks very interesting.