preggie, it depends what r you ok with too.
Filipino - Experienced one that work in SG before, you worried they too clever... Hygiene wise - I think so far for mine quite ok but again, it depends on luck.
Communication - English sure no problem.
Religion - If they are Christians or Catholic, you dont have to worry whether they can eat PORK or not.
Age - Try not to find too young one, if not miss home wanna go back, alot of problem.
Generally, my personal preference is Filipino, I cannot stand language barrier and I also dont have patient to teach also. LOL
Indonesian - Same as Filipino, find experience one also worried they too smart.
Hygiene wise - Always hear stories that when they first come, alot of employers cannot take it.
Communication - If new ones, good luck. Unless you know how to speak malay or Bahasa Indonesia. But I know normally they are very fast learner, like my aunt's maid, now can even speak chinese and cantonese! Superb!
Religion - If you really wanna employ Indonesian, I suggest look for Christian or Catholic, i heard they are generally better.
Age - Be careful to read the CV carefully. Some lie about their age.
Generally, of course if I talk about my aunt's maid, she is good.
Again of course, nowadays getting a maid is like gambling. See you "lucky" or "SUAY"....
My 2 cents worth.