Malaysian bands should really sing in BOTH English and Bahasa Melayu.
fact is because if you sing in Bahasa Melayu you'll get more fans and more people singing your song. But if you want to go far, you better sing in English. I had this situation where my friend was singing to One Buck Short's khayalan masa. She said that song is nice and that was the first time she ever heard of OBS. and I was shocked cause OBS has been playing around Malaysia for quite sometime. So yeah, sing more Malay songs ! and yes, not to forget English songs too please !