It was more entertaining. Every scene. The pacing was better in II than in I. The first movie dragged a little. (Most notably in the scenes where they were at the farm house or whatever with April and Casey Jones). Just my opinion.
Most sequels have more action than the original because they don't have to develop the characters and they can jump right into the action. The danger in that is sonmetimes you can over do the action and not write a good story. More action doesn't always mean a better movie a lot of times sequels seem more corny.
Examples: Iron Man 2 was very action packed but the 1st movie was better because they developed the character of Tony Stark. Gremlins is another example the 1st was more of a horror movie, the second was more of a comedy. Same thing with Ghostbusters.
TMNT is a classic as a kid I loved the action of the sequel but if I watch them now as a grown man and compare them 2 can't hold a match to the original. The original was dark, they really developed the characters and the plot. Not as gimmickey no Vanilla Ice No Ninja rap, and I hated how they did toka and razor