Learning "unimportant" languages useless?

im really craving to speak another language! should i spend my time learning a language that im interested in, but has basicly no importance ( im really interested in Afrikaans, maybe because its easy for an english speaker to learn?) or should i spend the time it would take to learn an easy language im interested in towards an exceptionally hard, but extreamly usefull/important language such as russian or chinese? would an an "unimportant one such as Afrikaans be useless? THX sorry for the essay:)