Most of the people, especially those who are not regular travelers, do not know what could be the most convenient and suitable seat for a flight and regardless the organizational structure of the type of aircraft, the selection could differ significantly.
However, all aircraft have a dead balancing and vibration point which is located near its center of gravity. This area is the most stable of the aircraft on its flights and does not match exactly with the middle of the plane as it comes to the distribution of weight and not of space.
A key criterion for the selection of suitable seat is the length of your flight, as preferences change between short and long flights. Undoubtedly a journey that exceeds the 6 hour flight, already exceeds the tolerance to stand still for any human being, regardless of service options of entertainment on board.
The other point to consider is whether you are traveling alone or accompanied, for which, in case of traveling in groups a shortlist of preferred positions to accommodate each group member most be conveniently done.
The last but not the least element to be taken into account, is the one related to temperament, personality characteristics of passengers, and even demographic and cultural peculiarities are worth considering. There are people who prefer to be near the bathroom, others to the kitchen area, others who prefer sightseeing whenever they possibly can, others who wish to rest during the trip or to read. On the other hand, there are older travelers, children, youth alone and in pairs and each individual or group with quirks of behavior.
Anyway, even if you achieve all of these preference criteria and chosen the suitable seat for a flight, there is still a key element to be overcome and it is that the seat remains free.