Full disclosure here: Stellar's a friend of mine. She allowed me to test this pack during development, as well as record staff ghosts. (I suck at this game, so all of mine are in last place. Granted, my main competition was heavyweight champion Kosmo...)
Both of the standard maps on offer have excellent flow. Shivering Night especially lets you go incredibly fast, both as a natural part of the course and as a reward for skilled driving.
Daytona Hell is still one of the best "love to hate" tracks. I didn't know it was possible to make it even more difficult, but then I hit lap 3. I'm not spoiling what happens, discover it yourself. It's brilliant.
As for the followers, I wouldn't expect anything less than stellar pixel art from Stellar. (Also I know where the Nova Fumo SFX comes from, there's no hiding from me!)