As for lessons, I made a pecan pie on Friday that was too puffy, a result of using the fresh eggs I buy from a co-worker who has chickens, The majority of the eggs are small or medium, like a bantam hen's. So, for recipes that invariably call for large eggs, I have to guess at the equivalency in small eggs, which can throw off the ratio of yolks to whites that are assumed in a recipe. The result is my pie had puffed as it normally does, but fell again when cooling, causing a cratering, even though the custard was perfectly set in the middle and not overbaked.
I guess the lesson is that even the subtle things matter, especially in bakinig. The pie is perfectly good, even if misshapen.
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Baking is a wonderful way to learn the Art of Cooking.
As I slowly learned proper handling of ingredients it opened opportunities for variations and substitutions. My favorite aunt's homemade pies looked like your pecan example.
We called them, "ugly pies" - looked awful but tasted amazing. Served in a bowl covered with ice cream . . . best pie Ever!

