I don't even know what the fuck is going on with Astralis but 6 man roster is very interesting. Their 5 man core is perfect, but fatigue is a problem, and if they can get someone to step in when needed that's gonna make things better in the long run.
The only issue I see is that es3tag might step in and be better than some other players. Let's hypothetically say he replaces dupreeh in a big event, and performs very well, Astralis take the win. Next tournament dupreeh is back, and he underperforms, and Astralis don't win. If this happens enough times, eventually the clear decision might be to -dupreeh, but that could fuck with the Astralis team dynamic. They are really dependent on the dupreeh-device-Xyp9x core. If anything disrupts that dynamic, Astralis might fall apart.