Current insanes are always of a very high standard build-wise!
Notable organics - Gladiator, 2B, Thunderbird
Notable landscapes - Celestial Resort, Mushroom Castle
For non-insanes:
Organics: Crocodile Head, Fossil, Yokai, Flow, Oogie Boogie
Landscapes: High Street, Halloween Porch
There's that one really pretty old insane that looks like a Chinese tower. Can't remember what it's called. Absolutely dreadful parkour wasted on it though rip