Obviously, entering more Grand Festivals and winning them will surely prove to be a rather difficult quest, but winning one should be enough to estabish you to a really impressive Coordinator. You'll already have what it takes to win Contests, and you already know the basics and the advanced strategies, so winning a Contest should be a piece of pie to you, considering that the most Coordinators that you'll face will be far from your league. It won't be the same challenge as the first time you entered, and after that you've won two Grand Festivals you'll probably be near to being undefeatable, and it'll almost be a bit unfair to the other Coordinators.About entering other regions and trying to win other Grand Festivals, im pretty sure that's more challenging and harder task to accomplish than winning just one GF from specific region. Its already hard enough to collect all ribbons and win one GF, let alone trying to win them in each region requiring great deal of skill and experience. Which with itself pulls higher reputation and recognition in world of coordinators.
I doesn't make much sense to me, no matter what way you put it. Travelling around in order to improve makes perfect sense, but I don't think you'll improve much if you beat Coordinators who you are being far surperior to in comparsion.
No, it's not the same thing with Pokémon Leagues. After you win a Pokémon League, you enter the Champion League, and even if you were to win it, you'd still be forced to improve and improve in order to keep your title as the Champion, meaning that the Trainers you'll face will often be near your level of skill. You'll always get to face Trainers near your level.
To me it was obvious that she wanted to improve as a Trainer and a Coordinator, but it was never obvious that she wanted to achieve a higher ranking as a Coordinator.Solidad obviously has higher motivations than being top coordinator of only Hoenn, and if there doesn't exist way to advance yourself and rank up after you win on Grand Festival i doubt she would ever went to Johto.
Wallace pretty much showed how there exists more to it being only contest master so far, and he is probably strongest coordinator currently in world.
Also, that thing regarding Wallace, what do you mean? Do you mean that they should try to become a Champion, or what?