Krakow, Poland versus Split, Croatia

My friends and i (F21) are planning to do a mini trip while we are already in Europe. We are stuck between Krakow, Poland and Split, Croatia. Krakow is really pretty, but it has a similar vibe to other european cities we're already seeing. however, lodging and travel are cheaper. Alternatively, Split is more expensive to travel to, but its coastal surrounds are incredibly unique compared to what we're already seeing. For reference the trip will be abt 3-4 days.