Actually, it's been proven that Exdeath is the best character to use, All Guard can block everything, but it takes timing.
I just...can't use Sephy, I've tried to make him my main, but his HP attacks are a little difficult to hit with, better than Jecht, but he's just not my kind of character. You'll be happy to know that he's mid tier, though.
And I'm slightly behind you in your Time Log. lol I've logged 250 hours as of yesterday, my Tidus and Gabranth have mastered everything, I've gotten a couple of Exclusive weapons like World Champion and Chaos Blade, and Megalixirs are getting ever the easier to obtain.
I'm gonna give some advice to new players, DO NOT SELL YOUR CHARACTER'S STARTING WEAPONS!!! They are crucial to getting the character's individual best weapons.