I like all the gyms, I shall analyse the best and worst parts!
The first gym was confusing - it never explained the purpose of the curtains which would confuse young children! and me. But I figured it out eventually. :3 Second gym was really annoying to get through but was easy once I went through there for the first time. The third was amazing, but confusing to figure out that you had to push the walls (notice the theme? BLACK AND WHITE ARE CONFUSING!) Uhhh, fourth was really awesome, tbh, and had a really awesome design too. Fifth was really annoying, but I really liked how you went down really low underground. Sixth was annoying but crashing into the wall was fun! Seventh was by far the most fun in terms of what you could do. It was also surprisingly the least confusing, although as a kid I always had issues with the ice puzzles in-game lool. The last one was amazing in terms of design but so freaking annoying to go through - you had to face everyone! :( And with a lack of easy backtracking, uggh.
Black and White definitely had some interesting gyms though.