Well, the game is way better than the first one, i'm been finish the game with dlc twice already, and the interface also improve here, like borderlands 2 than the first one. The character is almost the same, only a few changes.
One thing i like the best is also Handsome Jack, he is funny.

And there are plenty of more new guns compare to the first one, with more badass gameplay.
You should really get this game if you like the first one, i'm sure you will like borderlands 2 too.