Well that's because her main love interest is Nicky who's about my height (1.73m - but I'm a girl!). LSS on heels sees eye-to-eye with Nicky. Kevin and Wallace are still taller than LSS on heels. Ma Tianyu and Edwin are even taller.
I agree Nicky does look like he will have a lot of screen presence in the trailer, but I'm still not keen on the bed scenes.
I didn't see Guo Zhenni and Guo Xiaoting on stage though.