What makes a great dial?! Lots and lots of green!

Not necessarily.

Have a lot of green on a dial makes a ship very forgiving to fly and maybe even brutal when combined with the various stress inducers but I'd say that have lots of options with little, or better yet no, red may be even better. It all depends on your play style and how you want to use the ship.

I'd say the Defender has a very good dial as it is just missing the basic 1 forward and only has the 1 K-turn. There isn't a lot of freedom with it's greens and the slower turns may be red but if you're looking for speed that is the dial for you.

I did a dial-rating system a while ago.

Looking back, it was more of an index than a rating.

There was wide disagreement about the weighting I placed on green actions, but it might give you some ideas.