Don't store 3d camera tracking date in the AE project file.
The reason I am suggesting that is the auto-save function. The bigger a project grows the more important it gets - because crashes appear more often. The more cameratrackings you make, the heavier your project gets.
Waiting for the auto-save to finish really kills the flow as it can take up to 1 minute. Which you'll have to add to all those crashes and restarts.
I don't really believe in the background-saving idea (like photoshop does), because I fear not to have a good responsiveness while the project is saved.(like photoshop does not have)