I agree with you for everything except for the Powerleveling bit. I like Power Leveling, and think there's nothing wrong with it. It really doesn't matter where your levels come from, as long as they were obtained by legitimate, non-glitched methods installed in the game itself. Yoshi-P has affinity for power leveling, saying he appreciates people being able to catch up with their friends.

I'll repeat myself: It doesn't matter where you got your levels. What matters in the end is whether or not you know how to play what you're playing. Sure, leveling up via grinding and parties will give you a higher knowledge of how to play immediately, but if you are power leveled through most of the ranks, you certainly aren't hindered forever.

A good player will learn what he or she needs to know to be successful with their class, no matter how they got their level 50. The bad players, however, will rush to 50, get their artifacts, and just throw themselves straight into end-game content. Such players will be doomed to fail. Not because of power leveling itself, but because they didn't take the time to figure things out for themselves.