The following is a quick test: can plain images on white, cropped to irregular sizes, fit nicely in a square grid with uniform padding? I say yes, it works just fine. I'm always in favor of removing complexity and streamlining the process of creating content. Do the hard work up front to save more time in the long run.
How it works:
flex: 1 1 25%; height: 300px; padding: 15px;
Image: crop out white, upload
height: 100%; mix-blend-mode: darken; object-fit: contain; width: 100%;