That might be beneficial when you are actually engaged in live combat against a peer or near-peer where combat attrition and replacements is a major factor, in the peacetime, there is a lot of value in getting your best and brightest together so they can challenge and inspire each other.
The purpose of these elite units is more to help write the playbook and develop new tactics and strategies rather than to just have one super elite unit of ‘aces’. These units are basically going to be the instructors of the Chinese Top Gun, where they will play opfor against regular PLAAF and PLANAF regiments to kick their butts and then show them how it was done.