I wasn't disappointed, but it doesn't have the same epic opening as GOT had.
But also I think you are very quickly thrown into the middle of a lot of characters which is a bit confusing, so actually watched it two times and think it was better the second time.
I would have liked it to have been slightly longer than it was, again so you could get to know the characters a little better. Also, think it lacked a cliffhanger in the end.
But other than that, I really liked it and that it isn't afraid to, let's say present some pretty adult things. They didn't hold back on the blood that's for sure.
My guess is that over time when we get to know the characters a bit better that it will be pretty good.