I like these "no-bite" collars instead of the cone:
http://www.handicappedpets.com/acc/nobite/index.htm
As for stuff to put on the incision, maybe ask your vet. I know when my cat had a feeding tube and kept licking the insertion site, my vet put some kind of cream on it that tasted NASTY. I have no idea what the cream was called or if it was even intended for that purpose, but it sure did the job. My cat doesn't do cones.