Is it possible to make category and team area association more flexible?

Jane, the problem is neither RTC nor your solution, the problem is the manager.

The tool uses categories and you can have multiple per team. That is how RTC is created. You found the solution that works best and is the cheapest. There is nothing complex.  You could use categories such as Component 1 delegate Team1 or something along the line. Or Component1/Team1.

You can also come up with more complex solutions, that are not the best approach, if you ask me.

1. You can add attributes where you can add another team as secondary owner. Bad design. No impact on planning, it is actually unclear who is really in control. Needs Dashboard views. I would not do this.
2. Add some kind of crazy automation to have the component in another attribute and on save automatically  set the category with a manual override

In the end it will always come down to the category that is set for the planning. So the best and easiest solution is to come up with an intelligent category schema.

Personally without having spent loads of time on this, I would have suggested your solution. You have to work within the models the tools provide you with. Trying to fight against them only creates friction and costs.

To keep things simple (and make your manager happy :-), I would suggest the following Category Structure:

Component
Component/<ComponentA>    -> the team that works the most on component A
Component/<ComponentB>    -> the team that works the most on component  B
Component/...
Team
Team/<TeamX>                       -> team X
Team/<TeamY>                       -> team Y
 Team/...

A user that doesn't know what team should work on the work item would just set the FiledAgainst field to the appropriate component category, which would assign that work item to whatever team that works the most in that component (can change over time).
A user that knows what team should work on the work item would just set the FiledAgainst field to the appropriate team category.