^^That is a good point, it may just be a display screen. Either way, it does seem a bit diminutive in comparison to the rest of the interior. They could have maybe made the buttons on the sides of the screen a touch smaller so that the screen could grow by an inch or two.
It's not bad. I have the huge screen in my RAM. In a full size truck it's fine but there comes a point of diminishing returns as the screen gets bigger, along with unessecary distractions. In a small, compact SUV, It just doesn't make that much sense to have what equates to a big screen TV in your dash. The screen size in the Disco Sport is fine imho.
I think the size of the screen is fine. I wish the response time would be faster. I am not a fan of touch screens especially while driving; I'd rather interact with dedicated buttons where I can have tactile feel.