The T57088 added the possibility to upload multiple files at once but this is only really usable from the command line. If another script (e.g. flickrripper see T78506) wants to use it it's not possible to set a filename and filedescription for each. Especially the first is fatal and could lead to invalid upload tries when the file endings don't match (the second could be worked around by editing the filepage after upload).
One suggestion I have is to make the list a two dimensional. Still allow for each entry a string (the URL) and work as before or allow a tuple or list which contains each of the three values. This packs all information together (so not each list of data has to be handled separately) and also allows for entries in that list to not provide a filename and description and then use the defaults (like it would do currently).