People value products more if they have put energy/time in it.
That is…even if the product is not very beautiful/usable. But we have put a lot of effort in it…so it must be beautiful! 🙂
In stead of creating teams and channels for the user, let them be in control and let them create for themselves. Let them upload valuable documents in it. This way, they will value MS Teams more and will keep coming back for it.