Hi, ive been to many places across Turkey and i enjoyed all of them each with there own unique style, however the only three places i didnt like were marmaris, gumbet and alanya.
Gumbet is like
Marmaris too much like England for me.
The region of Olu Deniz is great, really picturesque and with the lively resort of hisaronu just around the corner it ticks all the boxes.
Bodrum is cospoltiation as is fethiye, with marinas and lots of shops.
Kusadasi is also a very nice resort with old town mixing with the new and good night life, Side is very similar. You wonder down conbbled streets and ancient arches on your nights out which add to the atmosphere.
I had a bad experience in Analya, the area is more popular with danish and sweds and as two english girls we seemed to get alot of attention and were constantly follwed by turkish men and felt really unsafe. I have never felt this before anywhere in Turkey.
Hope i have helped a bit!