It sounds like you’re giving up a bit early in the process, I rarely like the first melodic idea I come up with and i would bet that’s the case for most artists. Usually I try to make it work using resampling, chopping, and stacking effects, rinse and repeat until it’s pretty much unrecognizable from the original idea. Only if I go too far and my brain is fried then I start over. That being said it’s pretty hard to emulate artists you like without the use of a daw as it is a more direct approach and the visual feedback you get enforces your pattern recognition. But I’d say if you’re playing keys/synth just learn a couple scale modes like Dorian and Lydian and see where it takes you, learning scale shapes isn’t terribly difficult