That's probably why OP said it's open for discussion. But yeah herding (isn't the correct term flight attendants and not stewards?) the passengers would be diff

That's probably why OP said it's open for discussion. But yeah herding (isn't the correct term flight attendants and not stewards?) the passengers would be difficult. Perhaps the procedure should be, if everyone in your group is holding all their belongings - either in the aisle or standing in the footspace of an aisle seat (so rows C and D in a 3-3 configuration), then they can join the deplaning wave. But if you're standing in the aisle but one from your group is still crouched in a window seat and will need to grab their bag, and you don't want to abandon them, then you don't occupy the aisle go back to your (presumably aisle-) seat and wait for the next wave/go into an empty row so the crouched passenger can stand in row C/D, and wait for the wave to finish so they can grab their bag.