My biggest fear is that you will not be able to build a shared DC Cinematic Universe around MOS, or at least not a proper shared universe. From what we've seen, MOS looks like it will be a self-contained story much like the TDK trilogy and looks like it even has the same grounded feel of the TDK trilogy. If that is the case, it will not be able to be part of a shared universe and even if they try to apply the tone and feel of MOS to all of their other properties, the Batman reboot will face problems because it will need to have the MOS feel in order to feel canon with the rest of the cinematic universe but at the same time, doing that tone and feel again might make the reboot feel like a rehash of Nolan's movies. DC has basically shot themselves in the foot when it comes to shared universes because they can't really do one due to this or at least not a proper
one. Thus it looks like the next chance we'll get at seeing not only a DC shared universe but a proper one is in a decade from now.
Is this really a big problem? No. Not everything has to be in a shared universe in order to be good. However, I would've preferred to see a shared universe anytime soon because I think it would've been better to have a JL movie featuring versions of the characters that you got the chance to see grow and develop throughout their solo films as opposed to different versions of each character. It looks like now we won't get the chance to see a JL movie done like that till the next decade.