The fun thing about this game is that the tiles don't indicate what they do.
If you added arrows to the tiles, I think the game elemnt of this game would mostly melt away, becuase the arrows would end up highlighting the path the ball would take.
The jumps and the portals add much needed complexity and I think further levels could use some more tiles that further extend this idea.
Tiles that rotate the current dirrection of travel maybe?