Anyone know of a method/plugin that aligns and justifies planes of different widths and heights automatically?

[Roland R. kahlenberg]

AE CS6 introduced Snapping features. This feature was enhanced in AE CC. Snapping + grids should allow you to set these up quickly.

And if you want to animate such a setup in record time, then have a look-see at Layer Monkey here – https://aescripts.com/layermonkey/

HTH
RoRK
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