I do a decent amount of night flying of (40 of 255 hours so far in the -12).
The reflections are a real pain, especially when trying to take photos. I have the instrument glare shield, which I think cuts down on it a bit (it looks cool too). For the cost of that part, I'd recommend you give it a try. I had covered mine with black felt (which I talked about in a post from last year).
The best you can really do though is to minimize the amount of light in the cockpit by dimming things until they are barely readable (and to preserve your night vision).
But.. the canopy is the canopy.. and it will keep doing what it does best.. reflecting light in weird ways, seemingly always toward your eyeballs, keep you out of the wind, and keep the cockpit at EZ-Bake Oven temperatures all summer long.