My baby is 2 years 4 months old and he is not yet intelligible.?

My baby is 2 years and 4 months old and he is not intelligible yet. He is able to understand everything whatever i say or whenever i point at any object but is not able to say anything instead he shouts loudly. He speaks very unclear he only says 'Ma' and 'Dada' clearly. He does everything else like jump, run, play pretend with cars, books, ride a bicycle and has started blowing whistles also. I have also consulted a pediatrician and she told us "to wait for another 6 months and if he will still not be able to say anything then i will do a speech therapy". All the reports were normal. The only thing i want to ask that isn't there any other way to help him say perfectly, a proper way so that he will not be frustrated and able to interpret each and everything. I just want to avoid this speech therapy and want my child to become intelligible as soon as possible.