Agree 100%. One (just one mind) of England's problems has been trying to shoehorn in the "best players" into the team. Doesn't work in my opinion....picking a bunch of promising youngsters is not necessarily the thing to do, its more about thinking outside the box and bringing in players who can do a job in specific positions. They might not be the best players, but within the right team structure they are the most effective. Brian Clough won 2 European Cups with a number of journeyman players and Ramsey included Nobby Stiles in a side that won a world cup. I'm afraid we've had players recently lauded for winning 100 caps who should've been replaced by others because their records were ineffective.
As you rightly say, you need the best TEAM which will be the best players for each position. Example - Currently England had/have nobody on the left side of MF to link up with LB.
I reckon an England team of players drawn from Championship teams, if selected properly (right player, right position, right attitude, right tactics), would beat the current England team.