I have play many games. Many Japanese game also. I could said that Ken Sugimori really have the knack for designing human character and their outfit. The problem is, the story wirter didn't give them much soul and left them as bunch of pixels who wait to be beat out.
Well miss Toujours, there are many ways to make a game harder. There is no need to make every trainer in the game have competitive style battling although I agree if they could use some switching mid battle. I too, doesn't want the whole game become battle frontier fest. what I want specially to be harder is the Gym Leader, E4, and Champion battle. I want them to be much more memorable. If it too easy, it wouldn't so much memorable yes?
They could make restriction for each gym or special set of rules like the limitation to 3 pokemon or level capping so you don't overleveled the gym leaders. There are many way to make the game harder but still enjoyable by everyone.