Manchester United could certainly get over 100k with a fairer pricing system, Liverpool not too far behind. Clubs like Arsenal, Spurs, Everton, Manchester City, Villa, Newcastle could all be getting over 60k with the right pricing. It's just not going to happen though. Maybe I'm underestimating how much tv has taken over and killed football now, but all those clubs have large fanbases with a large matchgoing faithful, which is different from twitters fans etc.
Make tickets £10.00 for anyone within 1 mile of the ground.