Here's a touch that should make it easier.

Create a composition that's a lot larger than what your final video output will be, and hopefully large enough to hold all your clips in their positions so as they apear on screen at the same time. Position your shots in their in their places, and position them on the timeline for when they are going to show up in the video.

Now put this composition inside your standard video size composition and animate it's position/zoom/rotation over time with keyframes.

I've never done something like this with a composition of the screen size you would need for your clips. Perhaps there is a maximum screen size (I'm not sure) or perhaps a computer may start to struggle at certain sizes depending on the RAM (again I'm not sure).

It may be that you have to do this with a few larger compositions, and animate them along the time line (motion tracked to each other).

David.