Nara and Himeji are on opposite side of each other.. it might be difficult
u need to choose between the two if you can't do it in two days..
if you choose nara, the best place to view sakura would be Yoshino, which have 30,000 sakura
Yoshino Travel Guide
you are coming in late march? hmm am not sure if sakura will be in full bloom by then though.. will see how the weather goes this year , it might be early , it might be late..
are by any chance going to use shinkansen between tokyo and osaka???
you can visit nara on the 26th , then go to himeji on the 27th then leave for tokyo from himeji ...