Which usually benched players from the remaining teams do you think should always be in their nation's XI?
This means that they should start every game.

For me, its players like

Schurlle, Quintero, Depay, Willian, Mangala, Guarin,

mangala is a big no, he's had like 2 caps for the national team, and kosc, varane and sakho are all better. Willian I agree, he should be there instead of oscar who's been transparent since the croatia game. Schurrle I'm not sure, he did make a great impact yesterday, but maybe that impact is better when he comes off the bench. I'd keep gotze starting. The others I don't know enough.

Completely agree with Memphis Depay, one of our and world's best youngster.

But he's bench for tactical reason and it proves it has worked so far.

Durm to Höwedes at LB.
Lahm should play RB -> Kroos drops little bit -> opens place for Poldi/Schurrle
D.Luiz to CDM -> Opens place for Dante
Fernandinho to Paulinho/Ramires
Neymar to false 9 -> Bernard/Willian to Fred
Depay definitely

These are what I believe would work better, but who knows :-)