I think the two chibi characters suit your face shape better, but I'm also a fan of the green one in the top left. The pink one on the top left I think is a good option that matches your face while looking less juvenile/chibi if you don't care for those suggestions. I'll admit I'm a bit biased against certain Star Guardian and character cosplays though, having just been to an event with a lot of duplicates of Jinx and Ahri, so I'm always a fan of people doing less popular characters. Obviously you do you though.
KuroNekoCon- '11 : Radcon-'12 : Akicon-'13 : Sakuracon-'13, '14, '15, '16, '17 : PAX West-'11, '12, '13, '14, '15, '16, '17 : Rainfurrest-'15 : ChibiChibiCon-'17 : RenCon '17
Shy Gal (Nintendo Fan Design)