Speaking of consumers and things wanted or needed, I bought FPS weapon/arms pack on Unity Asset Store, import it into Unity, then go to the folder and pull out the fbx and texture files to import into LE4. Kind of sucks that this is the new normal but it's just the way things are these days as the Unity Asset store is the best place to get models.
Anyway, now I was tasked with lining up the gun which is kind of a pain honestly. To get it perfect in game with minimal restarts I added code to the gun script that allows me to change the position/rotation/scale with some keys. Once I visually have it looking good I print out those values and then set them in the script. All this to say that perhaps the ability to set position/rotation/scale of things during run-time could be something to look into. Currently I'm using this idea to line up the hip fire position, the aiming down sights position, and when running I want to tilt the gun downward as well. Without being able to modify these values during run-time it would be a nightmare of change values, restart, rinse and repeat.