That sounds exactly right to me: the Big Two either need to have a direction that they police, or they loosen the ties and let individual creators do their thing even if it means looser continuity.
I suspect I'm a bigger Morrison fan than you are (maybe?), but he's exactly the sort that needs his own corner to play in. He really should have just been given Earth-33 or Earth-18 or something: the Earth where Batman Inc and Final Crisis and Action could take place, continuity-free.