Oh, well, if you're putting fresh fruits on already baked cookie dough, I'd still suggest using a jam or jelly of some sort, but one that's kinda mild. This will help the fruits stay on, kinda like a glue. I'm actually very partial the the (I think it's smuckers) "Real Fruit" spreads, they aren't as sweet as jams and have lots of fruit bits in them.
The blue berry kind tastes really good, and would probably be good with some red fruits on it for color, probably strawberry or raspberry bits. Cherry preserves and apricot bits (dried or fresh) would probably work good too.