The whole hobbits & Gandalf plotline is pointless and affects nothing outside of it. The only thing that would be noticeable in the others if it was cut altogether would be the lack of relief when the show jumps away from Rhun. The whole plotline, over both seasons is not a story, it's an agglomeration of meta elements they thought they needed:
- Hobbits
- Gandalf
- Mystery boxes (Payne & McKay are former Bad Robot writers)
- Additional red herrings for the Who is Sauron? mystery
- More spunky female leads who are too adventurous for their society
- Magic stuff they can pull out their asses without having to work it in to the rest of the setting
The plotline is clearly just treading water. There was enough story for maybe two episodes in Season 2.
The only reason that they included it was because they don't understand Tolkien and don't care about Tolkien and can't imagine for themselves a story without hobbits and wizards. If they had been able to get past that, they could have focused more on the integration of Numenor into the war between Elves and Sauron. I guess I will wait and see if they even have Sauron go to Numenor to lead to its downfall. I mean it's one of those events in the Middle Earth chronology that has to happen to ensure that Sauron's body is lost.