How to avoid confusion between Percentage and Percentage Points?
Use whatever conveys the message more clearly.
This usually means to use percentages only for absolute metrics and use %-points for metrics which are presented as percentages (e.g. &quot;retention rate increased by 5%-points&quot; in your example).
From my experience you can expect almost everybody to know the difference. The only exception would be highly operational staff, e.g. blue collar staff on the shop floor, cashiers in a supermarket etc.
In the latter cases, or if there are language barriers (e.g. audience is not fluent in English) or technical issues (e.g. a bad connection), make the changes explicit. For example:

Retention rate increased from 10% to 15%
Potential revenue drop of 7% compared to 5% in the first scenario