Multitasking on the iPad has improved, but is still something of a sore point for power users, and barely used by most others. Ben Lovejoy at 9to5Mac made some recommendations that would mean multitasking on an iPad closer resembled how works on a Mac.
Gestures are faster, and while entirely unintuitive, they are easy to remember once you’re used to them, so I wouldn’t take them away. They can effectively be the power user option: the iPad equivalent of keyboard shortcuts. Second, while recognizing that an iPad is not a Mac, I can’t see any reason to reinvent the wheel when it comes to how you close or expand a window. Why not have the same Close, Minimize, and Full-Screen buttons we have on Mac apps? Sure, they would be tiny touch targets for a finger, but they could initially be a single touch target that expands into a larger version when tapped, and we then tap the specific button we want.