This is a pretty common thing for people to want.
Back in the openhab 1 days, I created a rule for JSR223 in Javascript that allowed me to easily group any items together into a single “scene”. I used a simple array structure to do it. The target value for each item could either be a hard coded value, or it could be the name of another item in which case that item’s value would be used as the target value when a role was selected.
That was quite a long time ago and I’m not sure if the rule is usable in openhab today. If nothing else, it might give you ideas as you think about how to implement your rules. Ideally there would be a scene definition ability within openhab core, but with the variety of possible things people might want to do and the complexity of the ui to do those things, I could see it getting really messy…