16 hours? When I were a lad we could only dream of 16 hours.
When I lived in the Aus bush and regularly flew back to the UK the journey was a nightmare. 24 hours on a bus got me to Brisbane. 24 hours and I wasn't even in another state, let alone another country. The bus arrived there a couple of hours after any planes left for the UK so that meant a night in Brisbane. 24ish hours in the air (with a couple of hours on the tarmac at Bangkok) and I was in Heathrow. Then it was a mere 20 minutes on a bus to the nearest relative where I could doss down.
The return flight was even worse. It didn't go Bangkok/Brisbane. It went via Bangkok, Melbourne, Sydney before landing at Brisbane which adds another eight hours to the flight.
Worst thing was that the plane would fly over my final destination in Aus on the way to Melbourne but it would be close to another two days before I'd get there.
I have done one worse flight.
During my time in the same remote town I decided to visit my bother-in-law who was running a biz on a Thai island. On the map it was a relatively short trip. I called my trusty travel agent and asked for the cheapest ticket. The agent found me a ticket with Royal Brunei. It's a dry airline but Darwin/Brunei/Bangkok was pretty much a straight line so it looked good on paper. It didn't, however, look so good when the tickets arrived and I looked at the times and dates.
To cut a long story short, it was 22 hours on the bus to Darwin, overnight in Darwin, three hours on the flight to Brunei, overnight in Brunei, five hours to Bangkok, overnight in Bangkok, day four was a shortish local flight to my destination.
Saving a few quid on tickets rarely pays off.