I start early every year right on opener (except this year but that is for other reasons). Weather is nicer, more coons are active, get a chance to clean out the skunks and possums before I get serious on canines later, and I usually can't stand to wait any longer than opening day, either.
In this area, I take a lot of nice coons right away...but I don't water trap much for them. I take nearly all of my coons in dryland sets well away from water. I get few kits and sows this way, and the males I do get run on the very large side. These older, bigger males seem to prime up much faster than their little counterparts, too. not sure why that is, but that has been my experience.
I just got into land trapping for them some time ago and never looked back. I don't get nearly as many as someone running a decent water line would, but I get enough to make it worth my while and again, they seem to run on large and prime end of things this way anyway so averages aren't hurt by the reduced numbers.
Jim-NE