You can squeeze in more emulators and/or game art by shrinking the images. Of course this means they’ll be lower quality, but it works.
Using the pixel theme helps too as it re-uses a lot of resources, like the background image, for example. The logos are really tiny too. Being that it’s a pixel art based theme, the low res gameart do to shrinking isn’t as off-putting as it may otherwise be.
I have 55 emulators on my pi without a white screen, most of them with at least some game art, the main ones completely scraped.
^^ my other hobby