In the show Star Wars: The Clone Wars, the Mandalorians were a war race and very barbaric, but latter a pacifist government took over and the Mandalorians became..well like Scandinavia. It would be cool to see Dragon Lord Ember change the Dragon Kingdom into something very similar, a kingdom that wishes to build rather then plunder. Opens diplomatic relationships, trade, and commerce with the Ponies and Grythons.Only for some to try and overthrow her because they don't like the idea of "Selling out" there culture.
Well, considering that under the previous Dragon Lord, the dragons didn't interact much with the ponies anyway... I fail to see how much will change.
The only truly antagonistic dragons were Garble's gang, and only because ponies directly 'humiliated' them... and they hardly represent the majority of dragons.
The red dragon was quite reasonable, and the green was pissed that Spike was eating from his hoard. The green didn't even follow Spike back and attack Ponyville afterward.
During the Migration, a vast number of dragons flew right over Ponyville... and a few even seemed to show off for the ponies watching below. No burnination of thatch-roofed huts occurred. No dragons swooped down and scarfed up fleeing ponies like Pony Mc Nuggets.
There's no evidence that dragons as a whole are hostile to ponies, but quite a bit contrary to that notion, as you can clearly see from the show itself.