Here are a few ideas:
Some large organizations break out some compliance issues into specializations that may, in other organizations, be part of employee relations, benefits administration, or other area. The larger the company, the more likely the area is to be specialized. For example, ADA accomodation request review and FMLA review/administration can be their own, specific areas. OSHA complaince may be under risk management in the CFO's area or it may be under a safety officer in HR, which may be under "compliance" or even its own hat.
Training and development is sometimes in HR, sometimes in it's own separate area. Same with recruiting (which is missing, and distinct from staffing by some definitions). Recruiting and staffing are separate tasks in larger organizations. Smaller organizations don't even have a staffing function by some definitions.
Attendance coordination (for monitoring and handling points based attendance systems)
Stock plan administration is a specialized area of benefits administration, you may want to consider using sub-areas.
I would remove "generalist" simply because if they are truly a "generalist", then they'll check all the boxes. If you have something more specific in mind like call center HR question answerer, you might call them something like Internal Customer HR Support Representative.
HRIT is often its own field because it will involve specific security issues (and compartmentalizes the access to sensitive HR data), investigative skills, and database knowledge that general IT staff will not need to know or not need to have access to.
Also, payroll is not part of HR in every company. It is often part of accounting.
Also, there are a lot of smaller certifying bodies out there that are pretty popular in the HR world. Did you want to include a wider array of certs?