Designs of the general look of soldiers (a.k.a. the extras) of the three houses of men in Beleriand around the year 455 Y.S. Will serve as cultural reference when designing the armor of the main characters from each house.
Yeah I can't help but do that too sometimes, and that's probably why that similarity is coming through here, even if it isn't really accurate. I think they're actually descended from the Haleth line, but some of that line was interwoven from the Hador lot...
Well, Aragorn has the heritage of mostly Beor and some of Hador, and Túrin and Tuor are also of that descent. So I did wonder at times what happened to House of Haleth. But I think that the nature of the people of Hador goes well with the Rohirrim, but they can also be reserved if need be, and that also points to Haleth. So if they're mixed from Hador and Haleth, then yeah, I think you might be on the right track.
There were members of both the Beorians and the Hadorians that stayed behind, never making it to Beleriand. The Halethrim that did so became the Dunlendings and their related peoples. As for the Eothoed (ancestors of the Rohirrim) and the Northmen from whom they descended, Unfinished Tales has this to say.
"The Northmen appear to have been mostly akin to the third and greatest of the people's of the Elf-friends, ruled by the House of Hador." (Unfinished Tales: Cirion and Eorl, note 4).
Also, the Halethrim did contribute to the parentage of the Peredhil: Hareth, mother of Huron and Huor (father of Tuor, father of Earendil), was the daughter of Halmir, who was the son of Haldan, who was the nephew and heir of Haleth.
No worries. I've just recently dived into the HoMe myself; sometimes you have to ask, "Now, wait... did Kiryandil make it to the final draft, or Valandil... was Anarion the older or younger brother?" It's a great resource for my fanfic/alternate history, but you start losing track of what actually got published and what didn't