I voted Leila. Many other actresses are pretty as well, like Charmaine, Ada, Jessica, Gigi. For the younger actresses, Tavia and Niki are pretty too. My favourite TVB actress is actually Myolie. But I think she fits in the "cute" section more. Also, Shirley is more of cute than pretty.
If I had to choose one from the list, I'd choose Charmaine Sheh. Niki Chow, Ella Koon, Michelle Yip, Nancy Wu, Tavia Yeung, Leila Tong, and Myolie Wu are pretty too.