I was wondering on the following.
Is there any idea that one should keep the Menorah burning for any longer than 30 minutes.
For instance, if using oil should one put in enough for longer than 30 minutes to lengthen the time of burning? As Chanukah is about persuma nisa, then is it a good thing to have candles burning for as long as possible?
Keeping the menorah lit more than half an hour depends on when you lit it. If it was lit before the stars come out, i.e. at sunset it should be allowed to burn until half an hour after the stars come out. Regarding keeping them lit for longer we are not obligated to have them burn for longer however according to some poskim there is a preference that they be allowed to burn longer.
Leket Yosher, Meiri, Magen Avrohom 672-3, The Mishna Berura 672-6 says that although there is no hiddur mitzva to add extra oil, however it is a hiddur mitzva to have longer candles ( my assumption is that they are more elegant).