Training wise, I would suggest looking through the Taming and Training posts on the forum for ideas, and Michael's blog lists the tricks he is teaching Kili and Truman.
Merlin picked up Turn very fast, and Shake, Nod, and Bat are others that don't require props and are quite easy. You also may notice some behaviours that Kiwi does now that you find cute and may want to put on a cue. I am currently working with Merlin on one where he seems to use his foot to scratch his chin (like he is thinking hard). You just need to give it a name and start saying the name and treating every time she does that behaviour. That is how Merlin "learned" the Wings trick.
Try a few and let us know how it goes. Good Luck!