A fourth Planner Group tier?

Right now there are three tiers for QC Planner Groups. I’d like four Group tiers in the Planner for larger projects like Kaiser that include multiple structures or phases. I’ve run into situations especially on larger projects that a 4th tier would be better for keeping the QC Plan organized in an appropriate hierarchy, as well as more flexibility in customizing checklists. AN example of the latter: when there are multiple structures on a project they sometimes incorporate different materials and systems, which would ideally translate to different checklists under a DFOW such as Building Skin. Is this easily implemented or does this have significant implication?