It's tricky tho cos Emirates B777 in Economy is not great so does depend on whether the route you're flying is guaranteed to have a A380. Flew them recently where one leg was A380 and the other B777, and could not be A380 for both legs.
I don't fly on widebody aircraft very often so I don't consider myself an expert, but long flights in B777 economy class with a 3-4-3 seat configuration shouldn't be legal
Oh yeah absolutely. All part of the research! Google Flights shows the aircraft type, which is useful (though of course the caveat is there can be substitutions on the day)
it's like picking the cheapest restaurant every time and complaining you get crap food
you have to research which restaurant to go to