The number of foreign player in the PL (and the Championship for that matter) is not the cause of the problem but simply the symptoms.
Some other countries create enough good players that they don't need to import better foreign ones.
Get rid of all foreign players from the PL and you won't have a better England team but you will have a worse standard of football in the PL, this will end up making things worse.
We don't have the same football culture as some countries, by that I mean that kids here have arguably more varied interests other than football - Rugby, Hockey, etc. and music, and other non-sports related interests as well as more focus on academia etc. - all of which are good things but it does "reduce" the pool of those kids interested in football. Go to many countries and football is all they do, they don't necessarily have the resources/interests in things other than football.
The problem is what we do (or don't do) with the kids that ARE into football and that starts at school. Too many (and this has been said many times before) kids that are taught to hoof the ball to the bigger kids and see who can kick the ball the hardest or who is best at dribbling around 8 players and scoring a wonder goal.
If the F.A. really want to make a proper difference they need to address this - no full sized pitches until late school age, focus on skill/teamplay/passing/technique rather than power, stop overzealous parents at games giving negative advice/shouting etc. More investments in proper coaches (Germany/Spain have something like TEN times as many fully qualified coaches as England does), more youth academies teaching the kids the better way to play football and so on.
The issue is the same with English clubs as well as the national team, people (well, "fans") seem to want to attack all the symptoms rather than the causes, many mistake the latter for the former too.
It's not all bad though, there are some impressive young English players in the game currently (Sterling, Barkley, Lallana etc.), just not enough of them.
Nice rant but are you aware of the way kids are playing football now? Do you honestly believe that kids of 9 and 10 are playing on full size pitches. Look at the FA website and read up about it. Changes have been made but will not affect the current crop of professional footballers. It will need to filter through as the kids of today grow up.