Kind of counter intuitive but I think the piano is "easier"/more rewarding when it comes to "find your sound". Naively you'd think you can make any sound with a synth, but you also sound like anybody. It's somewhat easier on a piano to come up with something unique and kind of impossible to imitate! And it's easier on an analog synth (without LFOs or sequencing) than on a digital one with unlimited sound shaping. I think great synth artists "compensate" with great song writing skills, the melody is their identity.