Run Razor, Xingqui, and Hu Tao together? I'm relatively new (AR 34) and I have all 4* except Fischl and Xinyan. My only 5* is Hu Tao, and I'm close to pity (72) on the regular banner.

Both Razor and Hu Tao 'require' Xingqui. So I figured why not run them together for now and let them take the field as their abilities go up. Is this a bad idea? Who should be the last party member? Diona?