Learn Finnish: Eikö ryppy ole yhä kauniimpi asia? - Isn't a wrinkle a more and more beautiful thing?

While yhä usually translates to "still", pairing it with a comparative adjective like kauniimpi changes its function. It acts as an adverb of continuous change, meaning yhä kauniimpi translates to "increasingly beautiful" or "more and more beautiful".

Why is the verb ole instead of on?

The sentence is a negative question starting with eikö (the negative verb ei plus the question particle -kö). Because the negative verb is already conjugated for the third-person singular, the main verb olla must appear in its bare connegative form, which is ole.

Could I use aina vain instead of yhä in this sentence?

Yes! The phrase aina vain is another very common way to express continuous change alongside a comparative. Saying Eikö ryppy ole aina vain kauniimpi asia? would mean exactly the same thing.

If we were talking about multiple wrinkles, how would the phrase yhä kauniimpi asia change?

If the subject becomes the plural rypyt, the complement must become plural partitive. The phrase changes to yhä kauniimpia asioita (more and more beautiful things). Notice that the adverb yhä never changes its form.