Such a sweet essay! I just loved following your journey. I am like your appreciative son: in my case I am blessed to be married to a great cook who loves to experiment: we keep a binder of "favourites" and a binder of "repeats" and both binders keep on growing. When a dish doesn't pan out, we both shrug and chalk that up to experience - but we also agree that it was worth trying.
But can you pick the best dish? No more than you can pick the most saintly guru. There are so many "bests" for so many different reasons. Some dishes come with happy memories. Some have intense or surprising tastes, Some are favourite for the comfort. Some for the complexity. Some because they just fill you up. Some because they spark discussion. It's not like a mountain range where there is a single yardstick. It's more like finding the most beautiful picture or loveliest song. They're just our favourites, and that is that.