Well rare chests are supposed to be best while uniques are supposed to be build enabling or niche items. Chest enchants only for rare chests would help balance that out a bit more even if it won't be what it was supposed to at this point.
Agreed, I don't see an issue with it besides the fact that people will feel that the two extra points are mandatory. Other than that, do it or don't, it's just another end game activity after you get your points.