The Gamoran Stormrider is now merely a footnote in the exploits of my little elf mage and her merry band of travelers.
After the (relative) ease with which we dispatched both the Abyssal High Dragon and the Northern Hunter, my faith in the toughness of these dragon fights has been restored. Maker, it was glorious.
We snuck all around it, watching the sky closely as it flew overhead -- but otherwise ignored us completely. We claimed a quarry, closed some rifts, and activated one of Solas' elven artifacts, and still it ignored us. Well, my little elf mage couldn't just let that go, could she? She's the herald of Andraste! She's the inquisitor! Sutherland would be slightly less enraptured!
So we approached it, oh so slowly, ever so carefully, and finally we got close enough for it to notice us, to decide we weren't just going to go away, to fire a giant ball of smoking hatred and death and, most importantly, lightning at us. Oh how I wished for a patented Shepard dive roll just then, heh. It was not to be, but we were not afraid. And why was that, you ask?
Barriers.
Lots and lots of barriers.
Barriers for everyone.
Courtesy of my little elf knight-enchanter.
With all four of the group at full health, using all their talents and powers of ruination, we whittled the dragon down to fifty percent health fairly quickly, but at half-health it decided to get serious about killing us. It took flight. Stupid dragons.
It flew all around us, dropping a couple more lightning balls on our heads, while Cassandra and Blackwall could only stand there and hurl curses at it. Sera tried to shoot at it, and my little elf mage continued to send frosty cold ice bombs at it... but the dragon could fly faster than them because of course it could. So, rather than expend precious magical energy attacking it, I rallied everyone close and kept up the barrier until the dragon decided to land again and fight fair.
Pretty crafty those dragons, I gotta say. It was at the precise moment of me being between barrier generation that it landed and attacked with another lightning ball. This one hurt Sera and Blackwall pretty badly, and in all honesty they never really recovered. In retrospect, I probably should have at least gone back to camp and replenished our healing potions. Oops.
When the dragon started flapping its wings and pulling everyone in close, Sera was the first to go down. With no guard or barriers of her own, she's kinda helpless in a close fight. Blackwall was able to hang with us until we whittled the dragon down to about twenty-five percent health (I think), and then the beast pulled it's flying trick again.
Blackwall was claimed by its second round of sweeping with wings, breathing lightning, and just generally being a pain in the ass. Cassandra was fairly badly hurt, but I wasn't too worried about her; she's a guard-hoarder, and she was staying on her feet and hacking away at the thing. For awhile. The two of us knocked about another ten percent off the dragon's health before Cassandra finally succumbed. Damn.
So now the stage was set. My little elf mage and her never-ending barrier versus the big bad ugly electric beast. This was the first time I really really really appreciated just how awesome being a knight-enchanter really is, for as long she continued to do damage to the dragon, her barrier never completely disappeared. The dragon clawed, it slashed, it lunged, it bit, it snapped, it shrieked, it clawed -- oh, said that already
-- but it couldn't touch her. HA! Take that, stupid dragon. My little elf mage stood toe-to-toe with it and did not waver. She threw frosty energy barrages at it -- which are a spectactular way for a K-E to rebuild barriers, by the way -- she threw winter's grasps at it, she threw magical bolt after magical bolt of frosty magic goodness at it until, with a final barbaric, "DIEEEE!!!!"...
...that's just what the Gamoran Stormrider did. 
Good loot, too. 