While I haven't been commuting for all that long I'm finding that the original route that I chose is still the best one, except that one street is now under construction. Because of that construction I found an alternate street that is actually better. This is only about 1/2 mile though so it isn't that different than the original 10 mile route.

My 10 mile commute in NYC is surprisingly mostly on marked bike routes. Only the last 2 miles in Manhattan are in traffic, the rest are on bike lanes or over the Manhattan Bridge.

I'm sure there are plenty of options, I've probably been on most of them in the past on the weekends when I did my more serious road riding.