It seems like the 5 invulnerable couriers restriction is something that will have a huge influence on how the early game is played and is something that the humans won't have any experience taking advantage of.
Courier isn't that important. It's being phased out across the recant patches. And there is a popular Dota mod with 5 fast invulnerable couriers.
Yes there is Turbo, no it's not comparable to regular gameplay.
So maybe playing without a courier at all would be more representative of the pub experience ;)