But since a large percent would actually be playing at the same time......it wouldn't help as much as you think.
The only times today when I have managed to successfully log in was early morning.

It's got a lot to do with timeframes.

Also.....there are a lot of people who have bought it but have yet to be able to make even a single character yet because of the restrictions.
Auto-logout for AFK would not alleviate the issue on it's own. It IS needed. But the problem is on too large a scale for that to fix everything on it's own.