How many emails do you have in your inbox? Do you really want one more? Your employees feel the same way. You are competing for their attention and so you must craft your message so that critical information gets through.
To reach your organizational goals your team needs to counterbalance ambiguity with good organization design. You need your employees to be able to talk about your goals consistently and passionately without a PowerPoint.
You must contextualize communication around your strategic objectives for communication is the lifeblood of your organization and essential to successful projects.