i would try to pick a color scheme so the different types of crafty ornaments will look unified. if you wanted to do popcorn and cranberry garlands, then cream and deep red would be great for dough, felt and paper ornaments. otoh, if you want to keep the color possibilities wide open, you could pick a motif (like a star or even a circle) and let that unify things. scrapbooking paper could be a really fun way to introduce pattern without having to create the patterns yourself (cut the shape from the paper, punching the hole for the string, & it's done!).
i was just looking through my winter/christmas back-issues of martha stewart kids for ideas. there was a tree decorated with "snowballs" which were just cotton balls but it really looked cute! there were also amazing figures (santa, snowman, etc) made from stacking buttons on pipe cleaners. pom-poms, felted wool balls, and pipe cleaners twisted into shapes also can be fun. my very favorite were the ornaments made from candy, though.http://www.marthastewart.com/article/candy-tree
this link only shows the instructions for one ornament. if you want the rest, i'd be happy to scan & email it to you! (ds1 wants to make these "without the hooks" so he can eat them, lol.)
eta: here's the link for the button ornaments . .http://www.marthastewart.com/article/button-ornaments