Drelmanes: A mod to make party NPCs act like in FO2 would be a bless. They aren't turncoat just because you accidentaly hit them. They become angry for a good reason, like when you kill Vic's daughter, or when you start a massacre in Klamath (Sulik's reaction is to be expected).
You'll have to load a older save game, that is, if you have one. :(
I have to warn you about another fault of the devs, they haven't added any option to push a NPC,
so don't enter in small rooms/corridors with your NPCs! They supposedly move after a loooong time waiting, but depending of the room/corridor you enter, and at what distance they are following you, you'll get completely stuck. I remember one time I got stuck at a room in Necropolis, I was blocked by Ian, and Ian was blocked by Dogmeat. Had to kill them, since it was my only save. :(
Multiple Saves are a MUST! I had so many similar instances with NPC's leaving me stuck somewhere! You occasionally have to be careful in FO1 about where you Save & Reload as well...
I don't want to spoil anything in the Game, but if there is a small single person wide way to pass being guarded by an NPC if you save and reload in the wrong place you could end up stuck.