Googled 'cake lifter' as well, and it looks like there is quite a variety. Also, There are some that look quite different than others... Which ones do you all suggest?
Don't know about buttercream, be interested to find out myself. On fondant, it was definitely fine for a couple days (during the time it was being eaten) - didn't melt at all as long as it was kept dry on top of the image. I will be...
I wouldn't say it was easier to make than MMF... Probably a little more labor involved actually, but the results are soooo much easier to work with and in my opinion the taste blows MMF away.
One possible idea for a tree is to take several pieces of thin wire and twist it together to look like a tree, and then dip it in brown royal icing... Did this for my cake titled 'October Birthday Cake' and it worked out pretty well.