Your marketing pieces will be more effective when you explain only one idea at a time.
Because one idea is easy for your potential customer to grasp but, more importantly, it is easy to remember. This makes it more likely that they will to talk to others about your product/offering because your single idea is easy to share.
People often get feedback from friends and family before they make a larger purchase, and if they can’t explain to others what you have, your potential client can’t get needed support to make a purchase decision.
In marketing, simpler is always better.