You know, I never quite got the love for the GC controller. I mean, ultimately I was fine with it, and it was shaped very comfortably. But the D-pad was so small and oddly placed it was basically useless, the spongy shoulder buttons never felt right to me, the C-stick should've been shaped like a regular analog stick, and I'd argue the odd face button layout hurt at least as often as it helped. Basically my fondest memory of it is the Wavebird's insane battery life.
Now the admittedly monstrous-looking N64 controller, that was my jam. Ugly, sure, but good button layout/placement, and the three-pronged design made it very versatile. I've never seen a controller since that made both D-pad and analog control equally viable.