Basically I would use both English and Malay to share. For Malay, it is only Malay. I'm not using Malaysian language or Indonesian language so save those nationalism brawls or claims in other sites. I do not speak nor write in either national languages.
I'm using historical Malay language based from the sultanate standard who patronize our existence here since 300 years ago. I am an ethnic Arab Moladi which is referred as Peranakan Arab of the past in the East (Asia Pacific). It describes the Arabs of mixed parentage especially those who live outside of our ancestral homeland in Arabian Peninsula.
Most of our people claimed the ethnicity of their mothers but I would not do that since it would raise confusion. The other reasons is to tell people that, Malay is just a spoken language for people of different ethnicity and it serves as the bridge for people in southern islands of South East Asia in cultural terms. You can be of any ethnicity to speak or express your idea in languages which is not tied to your ethnicity.
This site is dedicated for Central Asian Muslims. You can use this site to actually learn Malay in exchange of I am studying your rare language. There is a lack of materials to study Central Asian Turk languages as compared to modern Turkish spoken in Turkey. So, I'm trying to initiate something in favor of cultural exchanges between Muslims.