I personally think that the visor should be voluntary. As a former hockey player, who played at the Major Junior level, I found it a pain in the ass more than anything. It can distort your peripheral vision, and they can fog up at times, which is a real pain.
I can honestly say that the half visor, which is what is worn by a majority of players in the NHL, isn’t as protective as one would imagine. You can still get a stick to the eye, from under the visor. The only way to totally eliminate the eye injury thing would be to make a full cage mandatory, which won’t happen.
As for the rules governing helmets,
This rules did have a grandfather clause when it first came in. The last player to go helmetless was Craig McTavish. The last player before him was Rod Langway of the Washington Capitals. The last player who wasn’t grandfathered in who played without a helmet was Brett Hull, who, in the 1996 All-Star game, played without a helmet in a protest to demonstrate how little the players actually cared about playing to win in the All-Star game, to the point that he had no worries about getting hit.