Does anyone have experience transitioning their role as a data leader from reactive to proactive? If so, how'd you do it? Did you use any specific tools or resources to make it happen?

This is a very good question and the responses may vary depending on your organization culture and the perceive value of making informed decision with data. Data removed the emotions from making informed business decisions. In our organization, the desire to use Data Analytics was not fully embraced until the arrival of a new City Manager with extensive experience using data as a vital part of making decisions. He immediately started an office of performance management that tied directly with IT's Chief Data Officer to play a more expansive role and influence across the organization. 

Having a good strategy is important here, but the most important thing to enable this pivot is a relentless focus on finding ways to quickly deliver value to the business.  Put another way, you'll never become more 'proactive' by spending 10 months on an inwardly focused consulting engagement on things like building a data inventory or a data cleanup.  Focus instead on quick wins that the business is asking for, and use your successes to justify the addition investments needed to scale you out of firefighting mode.    

Build a data strategy, incl. what is needed to drive the business forward. A proactive approach and a set of goals that you are driving towards. Ensure you have the buy-in of the leadership team and that it is properly prioritised. This will allow you more opportunity to focus and drive forward as opposed to just dealing with ad-hoc requests.

Step 1 is always to get out of firefighting mode. Prioritization frameworks help make that transition. If your team constantly responds to ad hoc requests and one-offs, it’s hard to do anything except react. Next, you’ll need to carve out the time for planning. Develop a planning process that looks 3 months, 6 months, and 12 months ahead. Look at the business’s strategy and goals. Align the plan with strategy and prepare to support near and long-term goals. Identify and fill gaps. Call out risks and develop mitigation steps. Do some scenario planning to be ready for change.