I said it many times in these posts, but it is worth repeating. If you want to communicate to Angel Investors, your challenge is to be brief and exciting at the same time. Angels read dozens of plans and pitches a week, thus develop a short fuse stretched to its limit and a deja vu mindset. Every single word you use should be valued as an opportunity to break that fuse and lose your audience. Furthermore, the specific words used must strike a balance between creating "excitement, belief, opportunity-to-change-the-world, high expected returns" and projecting a perspective of "naive, smoke-and-mirrors, improbable deal, too-good-to-be-true".
Angelsoft is the software most angel groups now use to manage deal flow, presentations, investors collaboration, etc. They developed a great template for an executive summary. If you apply to present to a group that uses Angelsoft you'll end up supplying information in that format.
The same template, however is great for writing your executive summary of any deal regardless if presented to an angel group. Here it is