The translation is correct, as far as I know there is no idiomatic meaning to the expression.
Humans in general, in all cultures, consider large eyes cute, and we even attribute this to animals and inanimate objects. In Japan people might perhaps seem a bit obsessed about this, and you will regularly hear statements about people's eye size in Japan. If you google it you will find a lot of websites, YouTube videos etc , with recommendations on how to e.g. do your makeup in order to make your eyes look larger. Plastic surgery is also very common in east Asia for the same purpose.
You have probably seen in e.g. anime that the characters tend to have unnaturally big eyes, especially if they are to be considered cute contrary to characters considered ugly that usually only have a line drawn for their eyes. This is however not the only reason, large eyes in drawn content also helps conveying messages and emotions without explicitly stating them. There might also be historical reasons for it, as anime initially was inspired by US artists.
目が小さい
目が細{ほそ}い
are both expressions to signify small/narrow eyes. Whereas the opposite is simply
目が大きい
As for refractive errors, the following terms are used:
遠視{えんし} = far-sighted
近視{きんし} = near-sighted
乱視{らんし} = astigmatic