I would add that iCloud Storage capacity is not a factor in the way iCloud Music Library behaves. You might try holding down Ctrl+Shift as you launch iTunes in case that helps the progression of new matches/uploads. The other thing you can try is deleting the iTunes Library Genius.itdb file while iTunes is closed, which will force iTunes to regenerate it on the next launch. This file is intimately connected with the operation of iCloud Music Library. You can try selecting files with a status of Waiting or Error and use the right-click Add to Cloud Library option, along with File > Library > Update Cloud Library to push things forward.
tt2