They now are giving teams (slack knockoff) a free dialing number so it now can be used for phone conferencing without non-organizational people.
Onedrive gives you 1Tb of syncable storage per user, and 1TB per user pool for shared office resources.
I spent years as a google apps advocate, but seriously for the money, no one touchs what MS is offering right now. Google had MS hands down 10 years ago, and let google apps die on the vine. It is a damn shame too, because they were the only ones that have anything comparable.