If your image is 2048*872, then I would not expect any real problems with memory unless you have a weak system or a lot of other high resolution layers, etc.. If you have enough RAM then you should be good. If it starts to bog down you can set your comp window to half or quarter resolution while your working and/or turn of background layers you don't need to see until you're ready to render.
Creating the text in AE will not help. In fact, it would probably make things worse.
If you're doing these moves in 3D space, and are going from one newspaper or headline to another, then you may want to check out VideoCopilot.net for the free "Sure Target" plug-in and tutorial. It may work well for this project.