Did you try Horizon yet? I can give you a bit of info on it since I played it a lot, haven't played any of it in a long time so I don't know if it has changed a lot though recently, probably not.
Since it's meant to be played on Survival mode there are plenty of changes to make that mode less tedious, for example you can craft certain devices that allow you to save the game instead of having to rely on beds (or exploiting that save glitch), you have a lot more health compared to the vanilla Survival mode, you won't get a one or two shotted as easily but it is harder to keep your health full, stimpaks are very rare so you'll have to rely on out-of-combat healing through bandages and first aid kits, they heal slow and the healing will be interruped if you get damaged.
The combat feels better, you're encouraged to hit weakpoints instead of just going for center mass everytime, there's level scaling but it feels better, enemies won't get as bloated as vanilla, so overal the combat feels better, it's not a one-shot fest like in most other "realistic" overhauls, at least I prefer it this way, one thing I really like is how automatic weapons don't have their damage gimped when compared to single shot stuff, but you'll have a hard time keeping them fed with bullets.
The mod seems to be focused on the settlement system most of all, there's some neat progression stuff there, you can give settlers jobs and send them on mission through a menu, there are military, crafting and foraging missions, I might be forgetting a few but they all give you back resources once completed succesfully, there are a lot of additions in the form of new buildings and objects for settlements, honestly I don't use the settlements much but if you enjoy that part of FO4 I would say Horizon enhances that.
Outside of settlement stuff there isn't that much added, there are a lot of new consumables though, some new weapons and armor, a decent amount of new clothing and armor, it's mostly stuff that's modified vanilla meshes so you might or might not appreaciate how they look, I like them because they fit so well, considering they're practically vanilla meshes.
That's about it that I can remember about it, overall it's an improvement but it does get a bit overwhelming at first, there are some tutorial screens so it's not that bad, but you should still read as much as you can from the mod's page and the articles on Nexus, also you should know that compability with other mods is a bit tricky, most weapon and armor mods will work but since the balance is so different you will want to use Horizon patches for them, if available, you'll notice a lot of mods have horizon patches so hopefully you'll be able to use mods you like with Horizon.
