The only roadblock I've had in WoL is that one battle against Sonic with the Rayman spirit. That and almost any Legendary ranked spirit against Little Mac in a Stamina Battle. Also, I remember hearing that Nintendo looked at vids of pro players from the previous games and used that as the AI for the cpu controlled characters. I can't confirm it really, but it certainly feels like it at times. The only other reason I haven't finished WoL myself is because I've been letting myself get distracted by Stardew Valley and Subnautica. And hanging with my FC in FFXIV.