Appropriate ending, as in consistent within its own universe? Probably, I doubt they'd destroy the TV and novel series legacy something hurried and half-assed (ala Sandworms of Dune). Especially with all the time and budget they had to get it right.
Now will the ending be satisfying or complete? There's no way they can make everyone satisfied with the ending. They used the tagline "If you think this story has a happy ending, you haven't been paying attention" in their ads. I can also see them skimping on epilogue material too. Every other season had a huge exciting penultimate episode, and the finale was comparatively boring exposition to tie it all up. I'm not sure HBO will let them film a "talking heads" finale.