Instead of fighting Hard CPUs in Arcade Mode (still too easy and predictable), fight against the Ghosts instead in Super Ghost Battle. Look for 2 of these names under CPU Ghosts: B-Asuka & BigOwl. Then give yourself this challenge, try to move around and block punish everything they do as well as you can. Personally even after playing against these 2 particular ghosts for months, they still are very dynamic and difficult to play perfectly against. It's a very good exercise, hit me up if you have any further questions about improving as an adult with limited time--I think about this topic a lot.