Passing back to the goalkeeper when players are stuck with nowhere to go is a good option as long as they don't aim between the posts. Drill your players to make this move safely.
Make sure you drill your players so that if they're back passing the ball to the goalie, it doesn't go in the net. There's nothing quite like a missed kick or slip to give the opposition a goal and, subsequently, a goalkeeper to shoot at who has just had their confidence wrecked. If that happens it will be hard to come back and win the game. You need to equip your players with the skills and tips to make back passing to the goalie safe.
Tell your goalkeeper they cannot pick up the ball from a deliberate backpass.
When you coach backpasses always tell your players to put the pass to one side of the goal so that if the keeper misses it, the result is, at worst, a corner.