UI advise for a web application

We have a web application for Electronic Health Records developed for doctors and clinics. We have developed the application using ZK which makes the UI responsive. However, we now want to enhance the UI either using Angular and apply all the principles of UI.
We will demonstrate the application to the UI expert using the web and would like to have their expert inputs on the UI on each page.
We want to engage only those who have strong experience in UI development. This project will start small but if we are satisfied it can become an ongoing project for our other products too.
Brochure of our product is attached