Girls perspective - I have been to Tenerife, Spain, Ibiza, Malia and Zante and going by what you have said with regards to what your daughter would like etc, i would recommend Malia. It can be done cheapily and its a case of nice beaches to chill and the bars and clubs if she feels like it. Any place is 'safe' if you keep safe and are street wise and not irresponsible.
When a group of us 5 girls went, we went all inclusive which for the price was ok but drinks were limited and the hotel was a fair old walk from the strip. For these sorts of holidays i think you are better off going self catering as we all ended up getting food from other places most nights.
From what i know of these sorts of holiday destinations, i would put Magaluf at the bottom of this list, but thats my personal opinion.