I think sometimes our enthusiasm gets the best of us and we over-rate Schneiderlin. I don't think he is World Class or even one of the top 5 central/defensive midfielders in the Premier League. Definitely well in the upper-half though.
He is very good and he seems to be still improving when I thought he had reached his peak. Assuming Europe is still the immediate goal, I don't think we need to strengthen that spot, or Lallana's to get there. Lambert is also at that level, just wonder if he can stave off the decline at his age.
Clyne, Cork are at least average-ish and look to be improving. Ramirez and Rodriguez are similar, though more inconsistent and with higher potential. Puncheon is average, but useful. Certain situations he can be a key player, and at other times he should be on the bench. Don't think he is going to get much better than he is, but hopefully he proves me wrong. He's already vastly exceeded my expectations so it wouldn't surprise me.
Anyway, I reserve my Saints-colored glasses/insane enthusiasm for Luke Shaw. I had him pegged as a decently fast, solid defender. Which is what he was at the start of the year. The kind of player who doesn't play a sexy position and maybe isn't that exciting but is very good at what he does which is shutting down the wings and chipping in some solid crosses. But over the last few months he has been getting forward and it turns out he's incredible at it.
Lallana has great ball handling skills and Schneiderlin has a deft passing touch both or which contribute hugely to Saints' attack. And to be fair, because of their positions and the fact they are at this point known opposing teams key in on them making it difficult for them to do something awesome. A lot of times their skills are needed just to retain possession and draw defenders to them to start attacks. So really can't criticize them at all.
At the same time, when I think about the last month or so who has most often just absolutely toasted a defender and left them in the dust so badly that it immediately creates a man advantage for Saints it's Shaw.
I personally think he is the best player on Saints and should be playing for England already. Maybe as teams start to focus more on him as well, his effectiveness will be limited a bit just as has happened to Lallana but I tend to think not. Lallana has a few minor flaws. He isn't super-fast and he's a little weak with his head. They are flaws I can live with, easily given his comparative strengths. But I don't know if Shaw has any flaws at all. The only weakness in his game is a tendency to still make the odd silly mistake. Which is to be expected at his age/experience. In fact it's surprising how few mistakes he actually makes and at the rate he is learning I don't think it will be a problem for very long.