Be able to delete and rename entire directories.
I noticed just recently that you can't delete entire directories (i.e. folders) without emptying all the files out of them first. Tagspaces throws an error "Deleting failed. Directory probably not empty" when you try. As I am a big believer that in order to be successful Tagspaces needs to basically be a fully functional file manager, this seems like a important feature to include.
I realized right after I posted this that you can rename entire directories with Tagspaces. Sorry about that. But, I still think that the two biggest 'file management' features I would like to see in Tagspaces is the ability to delete entire directories as stated above and being able to select multiple files at once easier (i.e. shift click to select a series of files in a directory). Also, tagging directories would be nice, but not really that necessary. Thanks for the hard work!