Adding to the primary fermentor

Just wondering what people have added to the primary besides hops and what was the results. Making a pumpkin ale right now and I don't think it's going to be as sweet as I was looking for. Just thought that maybe I should have added some spices and maybe a little vanilla to the primary to help make it a little sweeter. Thanks for the responses.

I just added a gallon of pureed peaches straight into the primary of a wheat that wasn't coming out quite according to plan. Blanched them quickly to make them easier to peel, then sliced them up and threw them in the blender with a little tap water until they were about the consitency of a smoothie. Repeated the process until I had a gallon ice cream bucket full, then just sanitized my funnel and dumped straight into the primary. Don't know the results yet, but it's been a week and I see no signs of infection in the fermenter.

A few years back I did a spiced apple ale that called for a gallon of unpasteurized cider to be added to the primary. Again, I didn't boil or sterilize the cider in any way. That came out amazing!

vanilla and spice will not make it sweeter just more aromatic/flavored.
Sweetness from a pumpkin beer is going to come with a malty base and a higher mash temp if you mashed. If you used extract you may get more sweetness or crystal malts steeped. Also a less attenuating yeast will leave you with more malt sweetness,so if you end up with around 1.01 -final gravity reading or less it will be fairly dry. A 1.015 would be a good range for a sweeter malty beer. You can also get it by adding maltodextrin maybe lactose.I think you have to use a lot of lactose to really get that though but you can add it at bottleing if really determined but i would just leave it you probably will end up liking it especially in the bottle a month or two.
If you post your recipe we probably could tell you how sweet it is going to be, did you check your OG after you cooled your wort?
How do you know how sweet it is by tasting the wort? Checking a gravity reading after a week or two?