Wondering about spectating

Spectating anyone is always 3 minutes, and to what I know, its to prevent ghosting, which basically ruins the fun for most players. But there are always people who want to watch their friends play, maybe even teach their friends play, so 3 minutes behind kinda prevents that from being effective or fun. Lots of times people go "nice (persons name)" or "you should've played that differently" and always they have no idea what their talking about, cause it was 3 minutes ago.

My idea is that why can't there be a spectate mode live, but to prevent the spectator from cheating for a team, only let them pick one team to have vision of. The case where they spectate a friend, only let them have vision of that friend's team. Don't let them spectate the other team unless their also on their friends list. Let the friends have the ability to kick spectators. And if its a custom, make the 3 minute delay with vision of both teams an option.

If there's a reason for this not being an option, what reason is that? Is it a logical reason to make LOL fair? If so, is there some rules/options that can be changed to make spectating live an option? Spectating doesn't always have to be the whole game, does it?