These are really nice, good job!
Are you still having FOV issues/bugs? I have a weaponpack that has a pretty sophisticated ADS system, no FOV issues and the FOV triggers an animation as if you're actually holding the gun up/putting it down using I believe brick animations. The gun models themselves don't need to be animated in order to do the FOV animation.
The pack is private, but I've had these for a few years and I can't recall who gave them to me and they are more than likely MIA. If interested I can send you the pack and you can see for yourself if the FOV system is anything worth implementing.