IMO, it's not silly when that service, iCloud, was never really designed to do what you want. What you want, and is widely available elsewhere, is a hard drive in the sky.
Like a chain and its weakest link analogy, the iPad/iPhone are the weakest links in the iCloud "system" This would be because of their relatively small storage space.
You could do this if you wanted...
Do not sync your devices at all using the Photo Library. Move your photos manually from device to macbook, as you have been doing. Use iCloud to sync ONLY your macbook and the cloud. So the macbook is now the only source of photos for the cloud, and you are less limited by storage pace. You can expand the iCloud space by purchasing more if/when needed.
Use iCloud sharing to selectively put "some" photos back on to your iPhone/iPad. You create these albums in Photos on your macbook. Since they are part of the overall syncing process, anything placed in those shared albums downloads on to your iPhone and iPad. You could even publish these shared albums as websites instead and that way the photos are never on your devices at all, but websites you can visit. You can even upload images from your devices to these websites as part of your workflow. There are lots of options.