England XI: James Maddison, Harry Winks, who should be in the England team?
"The midfield three, are they chipping in with goals? Making assists? Not really.
"And I'm not sure about the centre-half pairing, who's going to play with Harry Maguire? I'm not sure."
Going forwards England seem in rude health - they have scored 14 goals in their three home qualifiers, scoring more home goals than any other nation in European Championship qualifying so far.
But who should play in midfield? And who should partner Maguire?
Pick your England XI below.
What did we learn from games against Bulgaria and Kosovo? Choose your first-choice England XI and share it with your friends
'Don't be disillusioned'
Leicester midfielder James Maddison was selected by BBC Sport readers for their team to face Kosovo - but was an unused substitute and is yet to make his England debut.
But despite leaving him on the bench, Southgate says Maddison - and other players who weren't involved at St Mary's - can still play their part in the rest of the campaign.
England played a midfield three of Jordan Henderson, Declan Rice and Ross Barkley in both games - with the likes of the ill Jesse Lingard, injured Dele Alli and Ruben Loftus-Cheek, Eric Dier, Harry Winks, Mason Mount and Alex Oxlade-Chamberlain all options in central midfield.
"It's very early in the season with their clubs, some of them haven't had a huge amount of club football," said Southgate.
"I'm expecting all of them to progress as the season goes on.
"I wouldn't want anybody to be leaving disillusioned that they haven't got on the pitch or that they haven't been able to play their part. To get in the squad at the moment is a challenge.
"It's a high level to get in the squad, especially for the young players. There are others out there that we think can come in and have a similar sort of impact."