More important how? I'm not sure what you mean, but I too doubt there will be hobbits. Possibly a passing remark or hint at early hobbit culture, but that's the most I'd expect.
If they were going to delve into hobbits, I think there is some history they could explore. For instance, the hobbits of Hobbiton view those hobbits across the Brandywine as less sophisticated, more worldly-wise, and "odd"; the latter mainly for being unafraid to go out on the water. I think it was said that Smeagol, centuries past, belonged to the "River Folk", a hobbit-like people very fond of water. There's probably an ancient link there that they could get away with showing in the Second Age.
I've always been interested in the history of Bree, how Men and Hobbits came to live together there, and its unique function as a crossroad for travellers and an independent city of trade. If memory serves, Bree was established in the Second Age, but I don't think hobbits arrived there until sometime in the Third Age. However, I've heard speculation based on the maps Amazon released that the series may delve into the war between the Witch-King of Angmar and the Dunedain; which, if true, opens it up to the possibility of seeing hobbits in Bree, or even in the war.
They could possibly also explore the hobbits' connection to the people of Rohan, or the development of the three "clans" so to speak (Harfoots, Fallodhides, and Stoors).
As far as non-hobbit things I'd be interested to see, I read an article suggesting they could show the Blue Wizards, which I think would be really cool if done right.