As I have been navigating through my career as a business analyst I've learned that the difference between good and great business analyst are the great business analyst embrace the underlying skills of business analysis. While being a BA generalist is required, having some specialties makes you more valueable.
For example, a business analyst who has a strong PM background will do a better job of managing and organizing requirements to combat scope creep and determining areas of risk (a PM favorite). A business analyst with a strong UX background will drive their requriements to a user interaction with heavy focus on user/stakeholder interaction needs. A business analyst with a strong data background will focus heavily on information flow and data needs, thus avoiding misses in information requirements.
Long story short, a good business analyst should strive to be good at most aspects of being a business analyst, and should be great in the others. The smart thing to do would be to focus on being great at the skills that will take your career where you want it to go.
Here a few courses I've found dig into specific aspects of business analysis to sharpen key valuable skills (don't forget to check the BA Reading List for books too)
Increase Business Productivity, Finish Your Projects, And Overcome Overwhelm (Step-By-Step)
User Experience Design (UXD or UX) is the process of enhancing user satisfaction by improving the usability, accessibility, and “delight” provided in the interaction between a user and product
Got projects? Use ideas from Scrum, Kanban, XP, and Lean to communicate requirements, plan, and monitor great projects.