I have no idea who was the genius that convinced America that Dental and Vision are not part of the health insurance. Most of the people have to have a separate vision and dental plans to cover their needs. However, it is making less and less sense to have either.
For vision insurance, I just went to one of the many places out there that gives you free eye exam if you buy 2 pairs of glass. And the two pair of glasses cost $69 or $79 somewhere there. While your vision coverage is going to be $10 $15 a month at least. Mind you that you do not need new glasses every year.
So unless you have a really compelling needs (have to have particular contact lenses or need frequent visit to optometrist), I think going out of pocket is the way to go.