What are the differences between the Echo and having Hydaelyn's Blessing? [Spoilers?]

[ExKage]

I'm not sure how much of this I'll be able to tease out by the end, but let's start with one thing:

Thank you! This ties that up nicely.

I don't even remember why the crystals were so important. Does Hydaelyn's blessing do much except.... What did it do other than it somehow protected us from Ascians? What exactly is it, to be blessed by Hydaelyn?

Edit: From what I remember of the end cutscene (I might have been too busy going "oh SHIT!") Midgardsormr was mad after sending the dragons to kill you. He speaks to you and he realizes that you have Hydaelyn's Blessing. You're worried, he tells you he won't harm you, and then he strips the weak Hydaelyn's blessing???? and makes a covenant of his own with you. For what purpose? I assume we shall find out in 2.55 and 3.0.

Dragons are not Ascian friends. Dragons and Dravonians are at War with Ishgard. Ascians control Ishgard.

WELP