Both have been great eras visually, but I'd have to go with Katy Perry's 'Teenage Dream' era.
Each video had its own chapter, its own look, its own distinct style and theme.
Style/Wildest Dreams/Out Of The Woods all kind of blend together, they have beautiful, natural imagery, very earthy etc. which is completely disjointed from Shake It Off, Blank Space and Bad Blood.
California Gurls > Shake It Off
Blank Space > Teenage Dream
Firework > Style
E.T. > Bad Blood
Last Friday Night > Wildest Dreams
The One That Got Away > Out Of The Woods
[From the 6 videos we've gotten so far; Wide Awake is superior to all of them bar CG]
1989 by far. and I thought Teenage Dream was going to be the strongest all around video era forever who would of thought Taylor of all ppl would be the one to snatch Katy in that department