There's no rush, but thank you for the perseverance :)
@Akylen, I've spent my evening on this... It's not that it's hard to add a 'Delete all' button, it's that I wanted to do the entire operation in a single request, meaning I had to refactor my code to allow for multiple IDs to be passed (which I also need to later allow for mass tagging on list pages.)
Well, what a failure. It made everything more complicated-- my API went from ~30 lines of code up to 50. Thankfully it's just 50, eh..?
I also met a lot of bugs, I think I've tested for them all, but if you get an error while adding or removing something, or if the operation doesn't complete with the requested addition or removal, please be sure to PM me so I can look into it!
It's 1:20am here so I'm off to bed... Sorry I couldn't do more.
I haven't added new games yet, but will let you know once I do.