I wouldn't mind a power-up for Sakura, but it's not what she needs.
Sakura is relevant to everyone she saves, but not to the plot. As long as she gets to influence/dominate the plot again, I will be happy.
This is the right idea. Power-ups are pointless if there's no plot relevance for them. As she is now, Sakura shouldn't need another power-up if she's to be involved in the plot.