Jolly Pumpkin/Nogne/Stone Special Holiday ale With Pumpkin?

My wife and I have settled on the Jolly Pumpkin/Nogne-O/Stone Special Holiday Ale as our baby beer. We are kinda tempted to throw in half a pumpkin into the mash, but I want to know what others think. There is a lot going on in this beer, so it might be on thing too many.

The exact recipe can be seen on Amazon’s preview, but not copied here for copyright reasons.

http://www.amazon.com/Craft-Stone-Brewi ... 1607740559

The ingredients:
Two Row Pale
Rye Malt
Munich Malt
150L Crystal Malt
Flaked Oats
Special B Malt
Chocolate Malt

Perle hops
Columbus Hops

Sage Leaves
Juniper Berries
Caraway
Chestnuts

What do you think. Will pumpkin be a good addition to this beer?
As a bonus, what type of yeast would you use in this beer?

Thanks!

Dan