No reason to change your stance. I also ride +-15 and I don't do a lot of switch riding. The duck stance gives you the advantage of being able to crouch very low. If you do any riding in tight trees, you know how this can be an advantage.
Some sort of rocker board powder board would definitely be nice. You shouldn't have much to worry about in the way of flats. I am sure the cat operator is well aware of problem areas for snowboarders and have adjusted their pick up spots and run outs accordingly.
Just let them know that you are getting your cherry popped and you want them to be gentle with you. If it turns out you can be more aggressive ask if they can accommodate that as the day goes on.