Agreed. I mean, it’s ok to try out and do the redesign of things, but having no clear mission about it except to look pretty is pointless.
Design is about solving problems, not avoiding them – if you’ve already picked some existing app/website/whatever.
I would suggest rather doing some made up product, branding it, define some goals for it and try to accomplish those goals. Seeing it from start to finish, and I believe somebody will definitely gain some xp doing it.