You can do all the technique exercises and theory studies that you want, it wasn't until I started to take a more philosophical look at my playing that I felt I had come into my own. Ask yourself questions like, "How do I play sad?" Have you ever had a conversation where you just listen to the other person rattle off nonsense until you can't take it anymore, and you just tell them how it is, right then and there? How would you do that on bass? How would John Coltrane do it? Richard Lloyd? Duke Ellington? Miles Davis? Or if you really want to get crazy, try to make your bass sound like Macho Man Randy Savage: CREAM OF THE CROP! oh yeah... cream of the crop... I'm the cream of the crop, Gene. the cream... Rises... TO THE TOP!