Keep in mind, you disembark 3, and cam then MOVE and ASSAULT as normal. All vehicles can do this. Vehicles are quite a bit more durable now, and require some decent effort to wipe them in one turn (even a rhino for example).
Also, some of the new deployment types can have you start 12-18 away from the enemy, so first turn assaults, even if the transport didn't move are possible.
It's really not as bad as it sounds.