This can include everything within the wide array of mods which change factions even in the slightest. Things like quests, gameplay changes, dialogue changes or additions, introductions of new factions, armor overhauls, complete faction overhauls. You name it. If it's faction related, I'd love to know about it — especially if it has anything to do with the Brotherhood of Steel. Even if it's something as tiny as a mod that changes faction dialogue to address you as a member (e.g. BoS calling you "Paladin" more instead of "Outsider," NCR soldiers addressing you as "Ranger," legion soldiers addressing you as "Legionnaire" if that even exists lmao)

My personal favorites are Drag's NCR & Great Khan Overhaul, Caesar's New Regime, NCR Rearmament, Book of Steel, For The Enclave, & For The Brotherhood. What are yours?

Everything you said including the mod for Fallout 4 by Elianora that adds a safehouse in the Railroad HQ.

I like what my friend thumblesteen did, literally all his stuff is pure fallout Gold, i also LOVE the stuff Dragbody does, like NCR ultimate overhaul and Legion will Ryse.