George Martin was fully involved in writing the ending with the writers of the show
When he does the books the ending will be the same , the battles will be the same just will have a lot more meat on it as you expect from the books
I thought the ending was perfect
SPOILER (Tap to show)
Martin effectively stopped working on the show around season 5, coincidentally (or not) when the drop off in quality first started. He's listed as a producer but doesn't have much involvement anymore.
Echo the comments on here re the ending. Broad strokes that'll be the end to the books too, with the exception of some major side characters (some of which are only given screen time because of ratings - looking at you Bronn...), the whole issue is just how rushed it is.
If the season is rushed, so is every episode, and the dialogue and writing suffer. It was all very flat.
The show's been a victim of its own popularity, and D&D seemed to be operating under the mantra "if it looks cool it doesn't have to make sense."
Hopefully Martin can release the books and we can get the ending fleshed out properly.