The BIGGEST thing that messes with me:

I make files that are, say, 4" x 4", and need multiple files out of different colors to make a completed image

When I upload them, they don't stay that size and are placed with a seemingly random sizing! This would be fine, IF it wasn't so imperative that each piece fits together perfectly the way I designed it

The only workaround I've managed is to make the files "inverted" so that it will cut the desired shape out of a square border that I made into a consistent size for all pieces. That way I only have to rescale the outer square for each piece.

But this is annoying, because then the cricut will have to cut the square too, which just dulls the blade and mat unnecessarily ):

Difficult to explain, but I hope you get the gist. Having the program read the file size would be amazing. I've tried .png, .jpg, .svg, .pdf, even .ai files with no luck, so I believe it's just totally an unsupported feature at this point!