The DeltaWing is not being different for difference' sake. It is another option in the new paradigm of technology in motorsport, which to be as efficient as possible (Audi's method involves pioneering engine technologies and diesel fuel, Toyota are hoping to break ground with capacitor-based hybrid technology, and the DeltaWing team are tackling the aerodynamics AND vehicle dynamics of traditional racing cars). The narrow track was merely a consequence of wanting to reduce the frontal area of the car for lowering the drag. Ben Bowlby then went and did his maths and found that you could build a car with what would be considered a very narrow front track, and a 'normal' width rear, that would only need half the horsepower, fuel and tyres (in lifespan terms, or tread width at the front) to compete with other prototype racecars. The fact it's able to run at Le Mans in the same laptime range as other production-engine based LMP2 cars (which still have around 150bhp more) is a testament to the gains in drag reduction, ground effect downforce, and unusual vehicle dynamics that Bowlby and his team discovered in their research, build and testing of this car.
If it's not an innovative design, show me all the other similarly shaped cars that can do what this one does. In fact, build another car with a 300bhp 1.6 engine and get those laptimes out of it.
A simpler test would be to get a Deltawing and widen the front track to the same as the rear, then compare lap times. There is no way that the small increase in drag of a couple of covered in front wheels is worse than the skinny front track that it has now. It goes against a century of race car development.
I do believe that speed can be found through compromise. Less power can equal more speed if it means less weight, better distribution, better packaging, less pit stops, etc. For example, a car with 400kw beating a 500kw one because its sacrifice in power has given it advantages elsewhere. That has been proven many times. (Just like F1 cars today carrying less fuel because of the weight advantage, even if it means a power loss.)
However, what we are supposed to believe with the Deltawing is that they have made a massive sacrifice in chassis dynamics (ridiculously skinny tack), but have made up for it with slightly reduced drag. They could have kept everything else the same (engine, weight, under body aero), they just needed to put the front wheels on some long suspension arms like a open wheeler car (yet they could still put covers over the wheels to reduce drag), but they decided not to. How is that not a gimmick?