Let’s not go too far down the path of gamers with visual disabilities. Speaking as a person with a whole host of vision issues which has considerably affected my lifestyle and my hobbies–including an absence of depth perception–I would feel quite patronized if allowances were made for my eyesight. If the rules call for range estimation and the group finds it an appropriate mechanism for the game, play on! Any adaptation I have to make to play a miniatures game is nothing considering the adaptation to everyday life I have already made. Humans are nothing if not adaptable.
Self taught, persistently behind the times, never up to date. AKA ~ jeff
More verbosity: http://petiteguerre.blogspot.com/