Four wheeled luggage is much easier than other types because you can push it
Take one suitcase and one carry on rucksack per person makes life much easier to manage.
Try not to carry liquids through security but if you do put them in a bag before security clear zip food back is fine
Have all passports in a plastic wallet
Put a tiny strip of masking tape on each passport with name on so you don't have to open them
Remember phone charger and power bank for flight . Download Netflix progs to watch. Headphones.
I pack a dress and cossie, pants and sandal in my case in case luggage goes AWOL.
Use packing cubes
Buy a boots meal deal to eat on plane
As well as above I pack hydrocortisone and antihistamine and a small pair of scissors.
I usually travel in thin loose harem trousers t shirt and cardigan or hoodie and trainers.
Take a spare luggage type padlock.