My first dragon kill was much the same... got slaughtered the first time, and my second attempt with better preparation including resistance from armour and potions barely hung on to survive. Barely had two people alive with slivers of HP and just Guard keeping 'em alive, and when the dragon finally died, felt more like slaying a dragon for the first time in a MMO than most single-player RPG bosses. Though admittedly haven't had many good ones in a long time to even sample from... these were maybe the best dragon fight I've had since Blackwing and Onyxia in Warcraft.
I did the Hissing Wastes one first... I hadn't known their levels, though I had been building anticipating ever since first seeing them in the Hinterlands and the Storm Coast, superb little scenes in their own right. I had been saving them because I wanted to do a focused dragon hunt later, and for some reason I had thought there were all an endgame goal. In the back of my mind, I had been building anticipation the entire game. Then, unknown to me at the time, I spent all night doing that epic treasure hunt, and near the end I was beginning to wonder if there would be a boss fight at the end. Genuinely had no suspicion that it would be a dragon. Then, as we begin to go into that valley, Iron Bull says "this is dragon territory"... epic... I was 75 hours into the game and I knew it was finally time for me. Iron Bull was screaming and howling with excitement, and even more so 15 minutes later when it died... and I was grinning ear to ear much the same.
The raw melee and guard system in this game can result in some really great fights, whether it's just bears on Nightmare 2-3 levels under-leveled or the dragon bosses themselves at about par level. It's not particularly difficult or demanding of execution... And it's rather easy to break post-Lv15 once your power begins to scale rather fast from specializations/purps...But if you go into them on the right difficulty at the right level, damn good.... the fights can tight and well paced which makes them exciting.
Makes me wish there was a hunting expansion, where the focus was clearing a great wyrm or beastly threat, where the 'War Effort' was focused on researching, hunting, and then killing great dragons, and then decorating Skyhold with dragon heads and treasure hoards. Though I'd be fine, too, with a more raw focus on the politics, and war and relief efforts, of a recovering Ferelden and Orlais.