The story for this installment is definitely an improvement over the first (not that Dusk was bad, by any stretch!) There's more magic, characters, and lore this time around. It also gets a bit darker, and throws some twists in that you definitely won't see coming. That being said, it doesn't feel forced either.

There are 4 endings (5, counting a "fail" state you can reach.)

The true SSS ending is really good, and of course the D ending is ok, there's just no love interest involved.

The two side characters ... their routes are much more fleshed out than in the first game. If you are going to follow all the routes, definitely do the side routes first. The endings take the story in completely different directions.

About those routes...
Heidi route is good, Fuhito route is really out of left field and is frankly a bit creepy