Should we merge the design studio research tree with the main research tree?

I know some people get confused as to how to build new car styles. Right now you need to research the design studio, place it down and THEN research new styles in a second piece of GUI.
Should this maybe just be another tab on the research screen? I’m thinking yes, although it would be a relatively empty one, compared to the others. It would still use different points ( design points) and require the design studio, so would that be even more confusing?
Would anyone think this is a bad change?

I think that this makes perfect sense from a user experience point of view.

Now about that Open Top Sports car?