Well here is this sentence I wrote:
Weil Einkaufszentren eines von wenigen Dingen, die das Leben auf dem Land weniger langweilig machen, sind, sind sie wirklich wichtig.
and I mean:
Because shopping centers are one of the few things that make life in the countryside less boring, they are really important.
Is the German sentence grammatically correct? How unnatural does it sound to you to have two sind next to each other?