I also think 4 is a good number for a collection, actually is the number of Pateks I currently own and I believe you can cover all the basis pretty well with this amount. And we also share a couple of references, like the 5110 and 5960.
On your other post, I said I prefer 5127 to 5296, but having 'curves' already in the collection, I would go for the 5296.
And for a dream watch: I have a 5960P and is my favourite watch by far. But given your plan and having an AC already, I would go for a manual chrono instead, ideally a 5070.
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