I've already expressed my opinion to Virgin CS on the move to charging. I wonder what happens if you're a family group of three or four - they guarantee to seat children with an adult, but nowhere do they say they'll try to seat the whole group together.
I worked in resort for Virgin Sun. The handling agent made it a habit of

up the pre-booked seat allocations so children were allocated away from adults. It took half a

season to sort out as the airport manager was a particular shade of dull and didn't figure out what the agents were doing wrong, or actively sought to do anything about it.
I still have nightmares about being the only rep on the desk, and trying to sort out 180 seat allocations with pax swarming around me.
Comes second only last minute check-in desk changes, and screaming at 200+ pax to 'not move a muscle', having to shift them across the airport in groups, with prospective line-jumpers trying to ram me out of the way with their trolleys. I had bruises along my calves for weeks.