I have to agree with [@Serpentine88], as it stands the ability to make lamellar quilts to cover tanks and airplanes basically negates the unworkable nature of the scales and in their currently proposed state makes them simply too effective.  If they were highly heat resistant, light, and effective protection up to small arms it'd make more sense.  After all the dragons need to be light fly, and if the issue is the dragons being powerful themselves making them have mega strong scales is a pointless means of protection as even if shells weren't able to penetrate the skin the shock of even a 20mm autocannon would be more than enough to result in fatal internal injury.

Everything else you proposed seems fine to me at least, but the scales should be taken down a notch.