Well my bananas turned out a little chewy and extremely sweet. After a little further research it appears I didn't cut them thinly enough, and they were too ripe going in for what I wanted. I might try spraying lemon juice on them next time because I hear that helps with the crunch but I think if I use the right bananas, cut them small enough, and leave them in long enough, I'll get what I'm looking for with just plain old raw bananas. The blueberries need several hours still.
Though the bananas are not what I'd want to munch on as a snack, we are going to try baking with them. They are so sweet that they would make excellent banan bread, and I think peanut butter cookies with these banana chips on top would be an awesome treat as well.
Even with only mild success on our first attempt, I'm pretty excited about the whole dehydrating process, it seems to offer a lot of potential when it comes to food preps. We need a Food Saver to really maximize though; I'm not sure how long this stuff will keep if it's not vacuum sealed.