I was always a huge fan of Woody Woods, highly strategic map and even more so if you take advantage of the Reverse Shroom. As soon as the next star location was placed, I loved the rush to see which direction the arrows were pointing and see who would be screwed over by it. Best soundtrack in the game, too. Never a disappointing game on this map.
As a kid though I always seemed to play Creepy Cavern, just loved the atmosphere of it. Chilly Waters is a definite classic go-to, and Spiny Desert is good to mix it up a little. Deep Bloober Sea was probably my least played as a kid but definitely has some cool aspects to it. No comment on Waluigi Island, speaks for itself tbh.