Roles rather than positions, though. Although you are correct, we did play more of a 4-1-2-1-2 shape at the weekend.
Anyway, I hope we continue with this more balanced 4-1-2-1-2, it gets the most out of both Mane and Salah I believe.
If we compare POP's average position map to another comfortable home win (the 5-0 against Watford in March), I'm not sure about any conclusion that we we're playing a different shape to most of last season:
I don't think the roles or systems have changed particularly. It's just different individual skill-sets and movements, which for me are always the most crucial element to these discussions; they alone can make roles & formations appear different, whether either actually are in terms of the manager's instructions or not. When Oxlade-Chamberlain plays for example, we look more of a 4-4-2, because he plays as a central winger. Milner and Lallana offer similar qualities in terms of supporting the wide areas, but because they don't have that pace on or off the ball, they appear more part of a central unit, both in terms of the naked eye and average position maps.
The key element on Sunday was Keita: his proficiency between the lines filled some of the post-Coutinho creativity void, thereby allowing Mané to stay 5 yards higher up the pitch than we were seeing at the back end of last season. That's why it appeared even more of a 4-3-3.
On a side-note, what I really enjoyed was Keita often moving both high & wide when Mané did look to drop deeper, which wasn't happening as much with Wijnaldum (or Can/Milner) in that LCM role last season, leaving us imbalanced (which has been a major problem down that left side for several years).
Many would argue that Wijnaldum was instructed to stay central to support Henderson or Can. While this may have been true, I would always ask 'why?' Was it because Klopp didn't trust Henderson or Can, as may on here allege? Possibly, but I think there is more to it than that. Think of it from a profit/loss perspective. Certainly against tougher opponents, there feels more to lose than profit by asking Wijnaldum to vacate his central area to move into wide areas, because his end product from those areas is generally going to be minimal. Whereas with Keita that obviously isn't true. He can beat a man with ease, and his final pass/shot is generally of a much higher level.