Now, I'm not very good with coding, especially involving probing into game ROM, but after figuring out that S.Atk and S.Def that are switched, I put the S.Atk EV value in S.Def EV bar and S.Def EV value in S.Atk, I check the pokemon's EV distribution in game and it's fine. I don't know if it's the AR code that's at fault, but as soon as I switched the EV value filling in Pokegen, it comes at as it supposed to be in the game (S.Atk value that I filled in the S.Def value in the Pokegen is back in the S.Atk value in game). I've never experienced this in your past release, including ones for gen 4 and the original Black/White so I am too surprised at this.
Okay, about the view/set streamlining, what cross my mind right now is, maybe each pokemon icon in the main window is kind of a button, so when it's clicked, it automatically displayed the respective pokemon's stats and after (the way it is right now is also fine), but after you edit the stat and you click other pokemon's icon, there's a reminder - maybe a warning - if you want to save the edit you do for the current pokemon.
Thanks for the early response, Codr.