It is a mystery

There's a Portuguese thing called rissois that's rather like these (but with less potato) that, well, start off filled with shrimp and wind up (in France) as a pear-filled dessert. You can get an awful lot of different kinds of filling in something like this!

Which is to say, going for something you like as filling and/or spices seems completely sensible. Same with "and what to we have lots of"; a whole lot of traditional regional dishes arise from "and in this season, we have a lot of..."

There used to be a Hungarian deli near where I used to live; they had a wall of paprika, and that's how I found out (thankfully by asking) that paprika comes in strengths from "make the deviled eggs a different colour" to "and then all my ancestors caught fire". Apparently you just need to know which one you've bought, too, they're not labelled for heat. So there's a potential for surprise with paprika, particularly bulk food store paprika. It's usually the colour-the-deviled-eggs stuff, but not always.