DD's tracks are featureless handjobs to fans of the spartan Mario aesthetic -- even ones that should be cool, like the ship and the freeway stages, are simplistic and lacking in real obstacles or environmental details.
There hasn't been a kart racer that even approximates CTR, although the GBA Mario Kart ain't bad -- it spruces up what made the original a classic. Mario Kart DS is tolerable but ugly; it's like a lightweight and uninspired take on CTR.