For plating, there are 2 major considerations: Balance and how narrow the tips are. I find that the tip heavy moribashis are a lot more difficult to control and are not as suited to plating fine details. Narrow tips mean how close to the end of the chopsticks do the tips touch. You want it to be touching RIGHT AT THE END, especially if you are using it to plate fine details.
For cooking, considerations are heat resistance, balance and weight, length. I believe these are pretty self explainatory.
Best of luck in your search! BTW Jon at JKI has a few. I fully recommend trying out any chopsticks before making a purchase.