Not sure other foreign players have the minimal amount of rest between games as those in the UK.
Even with lesser schedules the better teams get to rest players as well as the individual technical and physical demands being less because of the quality of the players in other teams in their respective leagues, particularly in Spain, France (PSG beat a mid table side 8-0 last night) and the low countries. I don't really watch Italian football anymore but the usual suspects are running away with it again I think (Napoli & Juve). I suppose you could counter that by saying we've handed a couple of hidings out and are running away with the Premier League! I do think its generally accepted the day to day grind of the EPL is tougher than their counterparts.
Getting replacements in for key players is a must - I'd love to have Fred right now (although I thought Taison was the better player) but I fear we might have to wait until summer.