While have a great liking for Breelanders and how they're described in LotR makes me think of myself to some extent, I still have the greatest affinity with the Northmen.
Being a Finn, they feel somewhat homelike and familiar to me. The north-eastern part of ME has always felt closest to me with all the Woodmen, Beornings, Dalemen, Esgarothians, Wood-Elves, Dwarves, Wargs, Orcs, eagles, thrushes, ravens and dragons. Enough variety of peoples and creatures but they don't feel alien to each other still. Also, places like Mirkwood, The Long Lake and The Lonely Mountain have something very intriguing in them. And part of my affection to that corner of ME is surely due to that my first ever RPG (when I was nine years or something like that and a few years older) mostly took place there and the game master (who was no one else as
Nogrod) managed to make the places so real and intriguing.
And I like the Northmen as peoples: Woodmen who know the forest, the urban and merry Esgarothians and the Dalemen with their lost kingdom. I like the somewhat mysterious Beornings the best, though: their affinity with animals, their brave warrior-spirit and the idea of them making honey cakes.
Besides, I've always liked the northmen Beorn and Bard as characters.