I guess that having a special dialog for reusable assets (maybe it could be merged to the swatches window) could solve the only case that would be missing after removing the gradient editor. I'm thinking about a dialog with a selector to choose gradients, patterns, or even "symbols" (user-definable objects to be used as clones in the document). For instance, that dialog could display all the available gradients in the document, allowing users to replace, merge (remove exact duplicates and leave a single instance) or remove them (one by one or choosing "remove unused" to automatically wipe unused definitions). It would be like a "library" dialog.
I'd love to know what you think about this idea, but I have the impression that it will solve a lot of problems and simplify several dialogs. It could be even a way to make "Vacuum defs" more obvious to regular users.
Gez