Bots used to pick a colour of their own, so the orange team could field yellow, pink and red balls and the blue team purple ones. Now every bot wears its team's colour, always. Your own ball still wears whichever colour you picked.
Bots also stick to the skins that are mostly team colour, like the slime, the hedgehog and the disco ball. The ones that were mostly grey or white with a thin coloured trim are now for players only. In your first few coached matches the bots wear no skin at all.
The coach covers more of the map. The first time you get near a speed pad, a portal, a gravity well, tar, oil or a team floor, it tells you what it does in one line. It also warns you the first time an enemy wearing Live Wire, Frostbite or Gravity Well comes near, and if Live Wire pops you, it tells you that's what happened.