U got 1 year so just monitor, freezing sometimes caused by bugs is unavoidable, bring it down also no use cos it could be certain apps doing it unless u r experiencing it often even after factory reset. Cos now no microSD card so more or less those are rule out, anything wrong not software related is definitely Samsung's problem. Sometimes cannot everything blame Samsung, could be Google's fault or Singtel apps fault, never know.
Since nowadays cannot take out battery, there must be a way to reset your phone like iPhone. For all you know, that info is in the manual which all of us can't be arse to read haha.
Naw, Like what I've mentioned earlier I've just get it back from the samsung service centre last week so there's not much apps installed and the pre-loaded apps has been disabled by using "Package Disabler Pro". Nevertheless, like what you've mentioned there's so many factor that might be causing the hanging and no use of bringing it to the service center as they will be doing factory reset only. My only option is just to closely monitor it.
Thanks again man for the advice and this sleeping beauty symptoms is sucks big time.

