I go back and forth on the park every time I play it.Most people hate the park, but I actually like it. It's almost like Walleye in that matches can swing back and forth frequently. It's also fun navigating the hills with the Charger. That, and the Tower is basically King of the Hill. =P
If there's any map I'm not great at, it's the Underpass. If my team is doing poorly, I find it very difficult to push ahead and try to take the middle. Given that my hit % with the Charger can vary wildly, it can make attempting to snipe very difficult.
The underpass is interesting because it's so linear. There's only one real way to get to the enemy base once you hit the middle, but multiple routes our. It's sort of the only map like this to this much of an extent and it leads to some pretty intense battles once you get in close. It can also be shitty if the enrmy hokds you back into your base though. It's definitely not my favorite.