This ranking sux. Level of matches I understand it's the level of difficulty games the team has played this season. There is no way Real and Barca are playing a tougher games than the English clubs.
Barca vs City league rivals elo rankings (41% vs 41% by wyscout):
Barca
Getafe 63, Cádiz 87, Villarreal 43, Osasuna 73, Betis 32, Celta Vigo 86, Mallorca 79, Sevilla 40, Granada 126, Athletic Club 37, Real Madrid 3, Real Sociedad 18, Alavés 106, Rayo Vallecano 66
AVG 61
City
Burnley 76, Newcastle Utd 11, Sheffield Utd 119, Fulham 47, West Ham 28, Nott'ham Forest 64, Wolves 49, Arsenal 5, Brighton 21
Manchester Utd 19, Bournemouth 70, Chelsea 25, Liverpool 4
AVG 41