Overall Balance
Well, this game is difficult to balance, especially without a tool as powerful as FFTPatcher. The changes to stat growths are a very good change, leveling in one job is not as pronounced as it was before. This allows you to switch jobs without feeling like you're wasting potential growth.
One thing I don't like is the starting stats of the Soldier class. Since Marche starts with around 30-40 less Mag.Power than a Hume Black Mage, he's pretty much a lost cause for the caster route. This is more of a flaw with the job system itself. If it was possible to make Marche start as a Blue Mage, or give Soldier similar all-around stats as a Blue Mage that would be pretty cool. That way you could go in any direction with him.
The change to abilities and their MP costs are good as well for the most part. (Although Sheep Count being a 4 range 1aoe sleep for 12 MP and Sleep being a 4 range 2aoe sleep for 10 MP struck me as funny.) Increasing the usefulness of abilities like Take Aim, Powerbreak, etc, that really didn't see much use in vanilla is great. (Except for Speedbreak, LOL, we'll get to that eventually.)
The change to caster weapons to include Mag.Power is nice, it makes them more than just a skill-on-a-stick. The sabre class of weapons is fun as well, as they boost almost all of your stats to some degree. Not much feedback here I guess, most equipment is either a straight upgrade or has a new skill to learn. The Circlet could probably use a boost, maybe +2~ Mag.Power just to let it compete with the Green Beret.
Enemy formations are where the current beta version I'm playing is sorely lacking. (hance mentioned that they weren't touched at all, which makes sense.) Nearly all the enemies are so underwhelming that I end up clearing every battle with little trouble. Fights against monster groups is sometimes a little touch-and-go thanks to some uber stat growths, but some Phoenix Downs and Cure spells can easily deal with their single-target damage. In particular, enemies need more abilities and reaction/support skills. Most things I've fought so far just have 1-3 skills in their primary job and that's it.
So What's Overpowered?
I mean, besides being awesome at the game.
Blind is severely devastating, and hance mentioned in Chat that it will be brought down from -50% accuracy to -35%. I think even -25% is fair, considering how much it affects, and that its duration is effectively infinite.
Wait in place. But we already knew that.
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SPEEDBREAK HOLY SHIT. I use this skill every damned fight, on every enemy that I can. Hance and I spent a good hour or so talking about why it's so broken, and the conclusion seems to be "I don't know, but it sure is good." On paper, it's just a 10-15% reduction in the speed stat. But, it lasts forever and it can't be removed in anyway that I've seen. (If you're a 1.3 person, consider lowering an enemy's speed by 1 or 2 points. It adds up to a lot of missed turns over the course of the battle.) It's basically a permanent mini-Slow. I love it.
That's really about it. I feel like using Blind is a crutch and feel bad when I use it. Speedbreak is sweet though.