Yeah, that's how i work. One draft with a million of different melodies. 2 or 3 are going to be used in a track and the rest is going to sleep.
Normaly i set up all melodies by ear, get inspired by other artist or my own crazy brain melodies. I often take a melody i quite like and change the rythm. Some melodies evolve.
I save the melodies as template and then i concentrate on the melodies i like, making a draft out of it and publish the finished track :)
Hope you enjoy this raw material!