You no longer have to do a near perfect run of a level to collect everything! Backtracking for elves is a great change. Still bothered by the ranking system discouraging upgrades. However, now that I could easily achieve 100%, unlike the first game, I found out it trivializes the game too much. I had so much more fun trying to perform as good as Zero canonically would. Optimizing a level to achieve A rank and a new form all in one go is a blast. OST is also much better than Zero 1.