I'm not sure if this is frameworks-plasma issue but I dont know where to place it. Please, move it where it corresponds if necessary.

Allow tagging in the "Save as" window. Like, for example, when saving a bookmark in a web browser.
Tagging the files we save should be something we could do at that very moment. Opening Dolphin, go to the folder where we have saved said files, and mark them to tag is a clumsy and time wasting process IMO, and sure many users don't tag their files as much as they wanted because of that discouraging process.
i think this could be achieved with a simple panel, like the preview panel, in the file picker, which had the tools that Dolphin has to tag files.