Only thing i'd say is that in the last decade expect for Chelsea (who are now changing) most of the top premier league teams style hasn't been the traditional way. Arsenal have always been said to be the Barca of the english game. Liverpool when Alonso was around and now under Rogers are playing a technical game. United with Scholes and City with Silva/Nasri.
this was actually the crux of the post I deleted. the english top clubs have varying european mentalities which makes taking the english parts of each team and trying to slot them as bits of a jigsaw into an english national team very difficult.
perhaps it's not that england has to many foreign players in its league but that it relies on too many foreign managers.
ok, a lot of national teams have players from all over the world but all spanish/italian/german etc players were all brought up with common ethos.
in italy, there are two foreign managers (and zeman almost doesn't count, having lived in italy since the 60s and coached almost exclusively there) in germany there is 3, in france there is 1, in spain there is... well there is 8, (although it should be noted that 5 of them are south americans with a similar ethos) in holland there is 1.
in england, there are only 4 english managers in the whole league. you could bung in home nation managers to make the total much more respectable, however for the most part, they're all absent from the top clubs. Only Man U has had a home nation manager for any length of time. liverpool have one now but after extended periods under french and spanish systems that's not a common state of affairs.
I think as puddleduck points out, plenty of english based players were fine fitness wise, to play in the Euros, Balotelli was one of the stars for example, it's a bit hard to blame the lack of a winter break in light of that.
however, I also think, looking back, england have always been a QF team, you need an exceptional batch of players to rise out of that. spain have that just now, germany look like they're getting there, but without those special players even the greatest teams slip back. Look at france, they didn't replace Zidane, Henry, Trezeguet, Desailly, those guys were at the very top of the game when france were winning world cups, without them they're just alright. Germany will need Oezil and Gotze to become stunningly good players if they want to topple spain. Good as gerard, rooney and the like are, everyone knows in their heart they're not among the absolute elite of world football.