Well, the Alchemy is a lot harder in this game. It's hard to explain though. Basically, due to the lack of a time-limit, they made some changes to keep it balanced. Some guy on gamefaqs typed up a pretty good explanation on how the new systems work. I'm too lazy to link to it and I'm sure you and others would prefer to figure it out next year anyway. Alchemy is still REALLY addicting. I've spent so much hours playing with weapons and stuff.
To me though, it sounds like you're biggest concern is about the characters. I can say the story is a lot more lively right from the beginning compared to Escha and Lodgy. I'm sure Stuart will back up that claim when he gets his copy. Don't need to know any Japanese to see that.
I don't know enough Japanese to follow the conversations well, so a lot of my impressions of the characters so far have been partially influenced by my imagination or what I think they're saying. That said, I think the cast are more interesting, and well diverse compared to Escha.
I think Homura, for example, already stands out just by being an homonculus wielding a sword and doing cool things in battle. His dialogue is written completely in hiragana and his speech is often casual, if I remember correctly. I get a cute and 'hip' impression from him even though the only thing I really know about him is that he's a treasure hunter and the girls think he's cute.
Linca isn't fighting anymore so... yeah. She's learned to be a lady.
Calm your worries. I can't guarantee, but I feel confidant you'll enjoy Shallie better than Escha come next year.