If you're happy with an Elite finish you don't need to do too much, you should get around 10 games against awful teams that are beatable on legendary, usually once you get the first goal as well things get easier. Win those 10 plus the featured games and you'll get an elite finish, might need to smash a couple of better sides on pro or something just to be sure but you can get a fairly decent finish without too much effort.

Don't bother grinding the higher rated teams, the AI is irritating af.