I think you will find that
Icmeler has what you'll find in Hisonaru, Ovacik and Olu Deniz, and
Marmaris would be like Fetihye - only more of everything and bigger tourist areas.
I love Ovacik but the distance from the beach and Fetihye is always a dolmus ride. Icmeler is in a stunning bay so beach much nearer though it can be busy. The centre of Icmeler is like Hisonaru x 4(or 5 or 6) so there's plenty of bars, restaurants etc to choose from and the popular ones have great atmosphere with a great welcome and a love of families (very like Hisonaru). I've spent time in some Hisonaru bars where there's only about 8 people, not something I've experienced in Icmeler! And the market is in Icmeler as well as Marmaris.
Where Ovacik and Hisonaru are difficult to separate, you'll find Icmeler centre and Icmeler Old Village similar - the only difference is that the old village has a good selection of good, lively bars/restaurants.
Hope you have a great time.