Write it in React, and if you run into performance issues, there are a bunch of well-known performance optimizations you can make which are easy to discover. It's a well-trodden path that many engineers have walked before.
Write it in your own vanilla framework, and you will effectively re-invent all the complexity of React, but in a way that no one has ever done before. It's easy at small application scales, but once your app gets large, good luck debugging the thing that exists primarily in your principal engineer's head.