Soooo many people are never going to root for the BardI think you can. The Witchers - and certainly Geralt - generally try to stay out of it, but the situation with Ciri makes things more complicated, though.
I think it's really just important to root for Ciri, Geralt or Yennefer. (And typically, that involves rooting for all 3.) But failing that, you can always root for Jaskier.