Hm, I thing you could:
1. Make the movement of the crane in fixed positions right above the toys (So that the game feels more intense and the pixel-perfect effect is on)
2. Try to make it seem like the crane rope with the magnet is a part of the crane (it sometimes seems like it just floats there)

3. Try to make the game as endless as possible. Because in the current version you lose when the magnet touches the toy, and the magnet will, most likely, do that, because it moves towards the single existing toy, and when the crane is low, the nearest toys are basically doomed either way. Idk how to change that: either make the up-down movement of the magnet more quick, so the main motivation of the player is to get the toy faster than the magnet, and set back the Y position of magnet to default, when the targetted toy is grabbed by the played, idk

But those are just my thoughts that I came up with on spot