worthiness of green pass

Thank you so much for your prompt answers. They are much appreciated.
Still we are agonizing about whether to buy the ordinary or green pass. You told us that the green pass is not really worth it and the only reason we are thinking of buying it is maybe the greater possibility of getting reserved seats.
We will be travelling during Obon from 7 to 26 august. We have to travel in weekends and we will probably be mainly travelling during rush hour as we would not like to start late as we like to pack as much travelling and sightseeing in a day as possible. We are 4 adults and it is a big priority for us to travel together having seats next to each other as we use our holidays for family time. If we book green seats would we have an appreciably greater chance of getting reserved seats next to each other than the ordinary reserved seats? We are thinking of reserving all our seats on arrival in japan.
thank you for your patience in answering all our answers.