If you are painting the plane red with black trim, then I agree with Ty. Pale blue or French gray with white highlights. I'd paint a red canopy frame somewhere in there too, just to give some more interest. Another alternative is a smoke gray if you can mix up something like that. On full sized planes, a bubble canopy like the one on the Akro is a real sauna, so guys tend to use pretty heavily dyed plexiglass. That is not really much of a disadvantage, since they aren't flown at night much.
I also use black sometimes, but your base color is already pretty dark, and your trim is black, so I don't think that combination works as well.
I personally don't like the way white or silver looks for canopies.
Good luck with yours!
Dave
PS--You didn't mention what your paint system is going to be. So I will throw in a random comment: If you are using rattle can paint, such as Rustoleum, I have had good luck painting the basic canopy and then just misting the edges with the highlight color. (For example, red plane, black canopy, silver highlight.) I have also mixed Rustoleum by spraying two different colors into cups, mixing until I liked the shade, thinning and then airbrushing the canopy and highlight. Just depends on how much effort you want to put into it. The hardest part for me is knowing when to stop adding highlight....a little bit more is not always better!