At present a low rep user (under 2k) can only make an edit suggestion of more than 6 chars, however when someone has taken the time to find to correct link it is a real shame the correction can help other users!
So I think link fixing should be special cased somehow.
(Also the checkering of a changed link need to be better than other edits, so a page that showed what both the old a new links point to (in frames) could help with the approving processes.)