Use smaller versions of the same chart type to compare across categories.
Adam Pearce charted minute-by-minute point differentials for NBA games during the 2014-15 season.…
The relatively new and lesser known time series visualization can be useful if you know what you're looking at, and they take up a lot less space.
We know spending changes when you have more money. Here's by how much.
Small multiples are great, and the right interactions can make them even better. A primer and a how-to.
Maybe you want to make spatial comparisons over time or across categories. Organized small maps might do the trick.
Make a lot of charts at once, line them up in a grid, and you can make quick comparisons across several categories.