Dude, this game rules! I always love a good twist on soccer, and this is just perfect - i hope you keep building this concept out!
im thinking:
rocket-league style boosts would be welcome
using the classic snake mechanic of getting bigger has so much potential - if there was 'food' all over the field and maybe getting bigger affects your speed or something? idk
i feel like the ball should fly further when hit as well, but thats something that would depend on the overall game
anyway i gave you 5 stars across the board. nice work.