That is such a
recipe!
You said there were three that don't drink coffee...do you like coffee flavored things...or perhaps just a pumpkin drink would be good?
Anyway, if you do decide to make it with the coffee, I'd double the amount of grounds called for. It is also really good with almond milk, if anyone in your group is dairy free.
And another helpful hint...if you have stick blender, use that to mix it up...it gets it much smoother than a blender.