Brightwing tip I just discovered in try mode

Brightwing can drop an instant Arcane Flare at her feet that has virtually no cast time or travel time. This quick cast works up to about 1 range before the skillshot changes back into a lobbed projectile.

Self casting and getting the bonus damage in the center is very difficult and probably impossible against some heroes, but you can still cast it between Brightwing's feet and her enemy's feet at melee range and get the quick cast.

This makes her Polymorph > Arcane Flare combo impossible to dodge and packs a real punch with the vulnerable talent. Q > W with vulnerable may be possible with quicker fingers but I can't pull it off.

Enjoy!