ahh I see

Taylor obviously. I would want to sing songs that have a meaning.

katy cause she's the definition of a global superstar
taylor was a non entity outside the US up until late 2014
and even now she's not that popular or successful outside the US
Katy is the full package

Obviously Taylor.

Younger, much more acclaimed, has 7 Grammys incl AOTY, way more album sales, and recently surpassed Katy as the biggest digital singles seller. She wins at everything.

Taylor. Nice, friendly, more acclaimed, loved by the GP.

Katy

Taylor because she is more successful and more respected.