IDK. Personally I struggle with the idea that a player 'needs' to get more than 5/6m a year. I mean if you're getting that for 6 years, I get that 500k a year adds up. However on the flip side... at what point is 'enough' actually 'enough'? Is 500k-1m (so 3-6m) really going to make that much of a difference when you're talking about a 25/36m contract? Sure it's a chunk, but either way you and your entire future family is set for life as long as you're not an idiot with it.
It all depends on what you're use to and your lifestyle. If all your friends are millionaires, you're going to have a higher standard of living than most.
Also, it completely makes a difference. First, it's making what you believe you're worth and your employer is willing to pay you what you're worth. Secondly, as I said before it depends to your means of living. A person coming from a developing country would be floored to make 30k a year. But to us that's nothing, it's basically living in poverty.