Britney.
Taylor can play musical instruments and write songs. But so can Britney.
Taylor can sing live but not very well, and also, her performances are boring.
Britney is not that great of a vocalist but at least she knows that and doesn't try too hard to make a fool out of herself unlike Taylor. And truth be told, Britney's dancing skills may not be as sharp as they were before but she's still better than most pop girls who try to dance.
What can Taylor do? Write songs and play musical instruments. (And don't give me that
sing live crap. Everyone can do it, just not as well as Gaga, Beyonce and Adele. Singing live is irrelevant if you suck at it.

)
What can Britney do? Dance, write songs, act, play the piano and serve performances that aren't boring. I'm sure there's more but you know what I mean.
Both are talented but Britney > the other girl.