Obama wants one to deal with ISIS/ISIL/IS what ever you want to call them. It's the modern declaration of war, only it allows a lot of hedging, like no ground troops, quit fighting after 3 years. The good old fashioned declaration of war, like we used on the Japanese in 1941, doesn't allow hedging. Which was a good thing. War is so terrible, so costly, that you want to get it over with quickly. Which means hitting the enemy as hard as you can to knock him out as soon as possible. Diddling around just gets more people killed.
We ought to just declare war. If we can't bring ourselves to do that, then the AUMF ought to say "all means, including ground troops and nuclear weapons may be employed at the commander in chief's discretion. Military force will continue to be applied until victory is achieved."
And we need language to define the enemy. Otherwise ISIS/ISIL/IS just changes it's name again and the AUMF is useless. Something like "All armed groups in the Middle East and North Africa who are not part of a UN recognized government, and, any UN recognized governments that fails to comply with UN Security Council resolutions. "
Frankly, I think Obama wants restrictions in the AUMF, so he can blame Congress when he fails to win to war. Obama doesn't want to deal with Islamist extremists in the Middle East. He knows he has to do something lest he get impeached or loose all credibility with the voters. He hopes that having the Air Force put on a fire works display will satisfy his critics.