I'd get rid of the mechanic of getting unnecessary doubles. Specifically with randomized drops/rewards. I play Animal Crossing as a part of my daily ritual sometimes. I'd check for new recipes, get duplicates, and stop playing for the day. It's just not fun to reduce a game to work like that.
I don't think that there shouldn't be any chance or grind involved, but I think an invisible coding quirk that makes a new or desired item inevitably drop would go to reduce some stress.
I think sometimes grinds like that can really mess up people who can just dive into games or have that compulsive desire to get 100% completion.
The sad part wrt Animal Crossing is (at least in New Horizons) the game actually DOES have the ability to filter the player's catalog and attempt to give them a reward thats's an item they haven't received yet.
It's just only used in two places as far as I know, Wisp's rewards and the 'better' reward if you finish the lost item quest by returning it to the correct person first try.