UI / UX Improvements to WindowsForms / Desktop built in C#

I'm undertaking a C# programming course, in which I'm tasked with altering and improving a partially complete desktop application. However, there is a non-code task to the assignment, which is asks us to look at UI improvements to the launch form within the application. The application itself is a three-screen desktop UI that mimics an marketplace for a coffee retailer. All information is persisted to a database.

I've done some basic research and like the look of three theoretical areas, namely Tab Order, application of Fits Law to UI placement and investigating Object Orientated Design Patterns.

I ask my question here of the UX community as its a discipline I'm not very familiar with but am of the view that some useful information might be had from more experienced professionals.

Any pointers or suggestions for things I could look into would be very much appreciated.