What's the best method of finding products with no/missing images with SuiteCommerce?

I'm not much of a developer. Is there a non-developer way to do this? It seems a bit strange there isn't a good method for admins or web store managers.

You could create a saved search, the filters will depend on if you are using site builder or SCA, for site builder there should be something like image url , for SCA I am not sure since the images follow a name convention from a folder, so not sure if you are able to identify which ones have missing images.

I have heard of people trying to use saved searches to mixed success

Yeah, I only know that for site builder it is possible, I recently had to check it for a migration and I used the image url but for SCA is another story.