I have a pretty eclectic collection. I collect species, certain sets, special promos, errors, and whatever speaks to me.
What makes me uninterested in set collecting is buying all of the cards that I have no interest in. What makes me uninterested in species collecting is buying duplicate arts of different languages or 1st ed/unlimited variants. So I fall somewhere in the middle.
I only collect specific sets where I love the entirety of the artwork. I only collect species in English with the occasional Japanese-exclusive release, but never duplicating art and only up to a certain point in time where I still have interest in the art/design.
I don’t fit nicely into the boxes of species collector or set collector, but I find that I am much happier this way to purchase what I like and leave the rest. 