Inferior in almost every way to the animated musical counterpart, the most disappointing change has to be that in the remake, Mulan is born with superhero powers because of some mysterious force called "Chi". This is the same sort of mistake which robbed Star Wars of the egalitarian nature of the Force by introducing the concept of midichlorians in SW1. Rather than empowering women, this suggests that women have to be born with special powers to achieve extraordinary feats.
This makes Mulan rather bland and uninteresting in this version. She has no character arc, no major struggles and no rebellion against the societal norms. Another problem is that Disney appears to be overtly anxious not to offend the Chinese audience. In the process, interesting characters like the talking dragon Mushu are jettisoned, many resolutions appear phony, the proceedings are humorless, and the supporting characters are dull. Even the CGI is nothing to rave about.
This movie will probably be a huge hit with the intended audience in China but for the rest, its just not worth $30. Just re-watch the animated version instead.