The ending is going to cause uproar and dissatisfaction - just because it's bound to. It's so hard to deliver a really effective final episode, and people are going to complain about it no matter what happens. One of my favourite final episodes anyone ever did was the 21st century Battlestar Galactica. The fourth series had become decidedly uneven before they got back on track towards the end of it, and the annoyance that caused as it proceeded I get totally. But, the final episode I loved because it completed the main story and still had 25 minutes to run. It then tied up all the characters and allowed us to say goodbye to them properly. So for all the flaws of that series (and it was still great television) I felt they ended it superbly.
But. Not everyone agreed! C'est la vie.