What about some veterans who are still going strong such as A.Barta, Festerling, D.Wolf, Gogulla, Marcel Muller, Pietta, F.Schütz and P.Reimer? No chance for any of them? Some experiance could be needed.
I am pretty sure at least some of them have retired from the national team.
On defense I would definitely consider some of the following, though none of them would be a clear upgrade over the others mentioned above:
Tim Bender
Marcel Brandt
Bernhard Ebner
Lukas Kälble
Oliver Mebus
Marco Nowak
Fabio Wagner
Marcus Weber
Also Emil Quaas seems to have taken a big step this season.
On offense there are even more options that we could look at. For instance Julian Napravnik (like Kälble playing college hockey).
Also Manuel Wiederer, Mirko Höfflin, Valentin Busch, Tim Wohlgemuth, Tim Brunnhuber and, above all for me, Taro Jentzsch should be considered in the not so distant future.
Along with Andreas and Tobias Eder, Maximilian and Magnus Eisenmenger, Alexander Ehl, Marco Sternheimer and Yannik Valenti.
Obviously not all of them will become big contributors on the national team, but if just 1 in 4 of them makes it that gives us some decent depths at forward, because there are some others I haven't even mentioned.
Elite talent is still rare especially on defenese and in goal, but the depths has gotten much better overall.