1) error while connecting
2) incorrect rating change
we can deal with connecting error by refafing over and over again, so that is "fine"
Spoiler: show
to deal with second issue I propose to have an agreement on 1v1 automatch games, when you play ladder game you should ctrl+k your ACU as soon as your opponent dies, so game will be resulted as a draw and for both players rating will barely change, so we avoid incorrect rating change.
Guys who stopped playing cause of rating issues, would you comeback if people will agree to "draw" games on purpose? so you can at least play for fun...
Edit: i don't propose to invert game result (e.g. winner should ctrl+k) because there is a chance that eventually rating will be recalculated