What about some cross-over ideas.
These are always popular with the design houses. I've reviewed a few excellent concepts for students.
SUV <-> sports car ( Renault have done this recently )
camper <-> runabout.
Student did a really neat one of camper to drive to site but then out of the front it detached and it became a neat soft top 4 seater. benefits obvious.
think about some of your own. How about road car to track car ?
The Deronda is interesting, but so far they've not published the window and side luggage designs. But I've discussed them with the company owner when he was at Knockhill. So if you're interested get me on messenger.
In building a design portfolio, the intended use and fit to the differnet purposes are as important as the drawing and engineering.
Also, design studios aren't limited to just reviewing work on cars.
How about lawnmower, hoover, hand tool, games console. All things which can show aspects of solid thinking in usability, looks, form and function.
The other thing which car design houses like is the portfolio expansion stuff. A lotus off-roader or a Rolls-Royce SUV or a Land Rover sportscar.
"A woman without curves is like a road without bends, you might get to your destination quicker but the ride is boring as hell'