Bunpro already supports multiple answer inputs, e.g. Cloze and ClozeFlashcard. IMO, a valid new answer input would be Multiple Options. Basically you’re presented with a cloze sentence and you pick the 1 correct option over 4 possible options.
This may lead to slightly worse retention than regular Cloze but it’s also more interactive, fun and faster. Importantly, it would solve one of Bunpro more persistent issues, i.e. similar grammar point with the same meaning. Either way, it would be optional, same as ClozeFlashcard is today.