I am going to write more about something else which seems to be overlooked.
Passing football without high pressing/geggen-presing is suicidal.
That's why both Pep and Klopp value pressing and quick ball recovery so much. You won't normally see Man City and Liverpool being exposed to counter-attacks. They either steal the ball or make a tackle. Klopp uses to say that winning the ball in the opposition third is the best creative player you can have because you are only 10 - 20 yards from the opposition goal when you win the ball back.
And what do we do? We always start our attacking movements from the back. First of all, opposition goal is far away, and if you run 70 yards you get tired when you get there and you can't shoot properly. Second, you give the opposition all the time they need to re-group and organise defensively. Third, opposition preserve energy, so they can counter-attack you, and you get tired.
But even with this tactics we could improve tremendously if we crossed the ball more than we do, and of course shot more. The trick is in numbers. The crosses and shots don't even need to be accurate. When you cross and shoot it creates panic in the opposition lines, and that's more important than being accurate. And there are rebounds.
A couple of days ago I watched the Liverpool v Leicester match on TV. Liverpool had 28 crosses!!! "Effective time in football is the total amount of time that the ball is in play in the match, after removing all stoppages due to fouls, ball outs, corners, substitutions, injuries, goals, and so forth. It expresses the amount of flow in a football match. It takes some skill on the part of both teams to have a match with close to 70 minutes of effective playing time, or 40 minutes for that matter if one team is acting as destroyer." OK, let's say, Liverpool and Leicester played 70 minutes effectively, which would mean that Liverpool put in one cross every 2.5 minutes.
Why is it extremmely important to press high and keep opposition under a constant pressure when you play passing football? Because if you don't do that, then YOU are in trouble, just like the Swans are in trouble game after game. We have to labour to create something, and that's normaly of low expected goals value, and when opposition steals the ball from us they create huge chances with high expected goals value and without actually need to work hard.