For the eye sight question, as well as 20:20 vision there are three important factors
'If you need correction the refractive error (the amount of correction) must not exceed +5.00 dioptres of long sight or -6.00 dioptres of short sight'
'Astigmatism must not exceed 2.00 dioptres.'
'The difference in correction between each eye (anisometropia) must not be more than 2.00 dioptres'
This is all from
Class 1 medical certificate - Flying Academy but I read the same material on the official requirement list too.
hope that helps.