I think we can simplify this with just an option to discard the suggestion.

Having a direct option instead of a menu, seems more direct and we can still provide feedback to the recommendation system: positive (suggestions that the user starts translating) and negative (suggestions that the user discards or does not start translating after a long time).

This is great. We need to check which indications of quality or impact we can get to surface them to our users.

I'm a bit concerned about this option being hidden under "ongoing translations", since users in other views (e.g., viewing the suggestions list) may not find an obvious path to start a new translation, and allowing users to quickly start a new translation is one of the goals here.