Radical updates to the user experience are generally a bad idea. Usually, you simply iterate on an existing "good enough" experience in order to maintain continuity and prevent a jarring change to the user. This was one of those rare opportunities to make a massive shift by bringing an old framework, kicking and screaming, into a modern context.
This was not only a major update to our web presence as a company, but a full re-evaluation of the User Experience and User Interfaces of our suite of web-based products, each of which has its own data constraints, user behaviors, and client demands, and hadn't been meaningfully updated in ten years!
A lot of research was needed, and it was all hands on deck. I created shared spreadsheets with each of our main competitors in order to divide and conquer with help from several other people, across departments. Then surveys were sent out internally to gather insights and interpretations, in order to maintain some semblance of objectivity at this critical stage of the design process.
Next, it was time to develop many different static mockups, and even some interactive mockups. I taught myself to use a web-based design tool called Webflow in order to make this process as efficient and accurate as possible.