Personally I think the gradient needs to go, the sine wave is too big/long, the z is too far away from the vertical line, and the green in general doesn't match the vibe they're trying to give. The z is kind of just sitting uncomfortably on top and the overlap won't look too great when it needs to be smaller. The z needs better alignment and something needs to be done about the overlap. Also the sine itself isn't aligned to the line properly, and at the least the leftmost edge of the wave should be thickened and meet the vertical line by dropping down at a steeper angle so the leftmost edge of the wave becomes flush with the left edge of the green bar, not come to a point as it does now.