If you buy new the players, the second section will get better but the first section will get worse.
Not necessarily. That only happens if you do a total overhaul or something. If you buy 1 star player (who ends up being your highest paid player) it won't negativey affect your survey much (even if you sell him a couple of weeks later), but it will boost your ratings.
I had both at above 4 balls last season. This season the latter has dropped to 3 balls, but the first is still at 4.5 balls.