The problem with that is that Fallout 4 has so many mechanics that restrict modding. Then there is the voice protagonist, so if someone would remove all the story from Fallout 4 and nonsense quests it would need voice actors to replace the voice for the new quests and story.
I am not sure if it can be done yet without Fallout 4 SE, and since the SE people moved to Skyrim Special Edition I have no idea when they will return to FO4.
Then we also have the fact that Fallout was never as attractive to modders as Skyrim (and we can't forget the modding restrictions and how many things are hardcoded so they can't be changed) so most modders moved to Skyrim Special Edition because they have no interest in Fallout, and with the next game from Bethesda being almost assured another TES I don't think modders will return to FO4 either.
Unfortunately the truth is that almost no one (of the great modders that this project would need to be part of) wants to mod Fallout 4 anymore and no one would want to do something like this because it would take years and modders are not even sure if it is possible due to hardcoded stuff that Bethesda put in the game and the lack of SE.
FROST is the easiest way of doing away with the story, since it just disables all of it pretty much and makes the game just be a shooting frenzy. And even that will take quite a while to be totally completed.
I would say that this will probably have to at least wait for the SE to be made, and/or more great modders to return to work on FO4.