Having a library of Pre-Designed Conversion Focused Templates would be helpful
2-Step Opt-In Form, Slide-In from the corner, Content Lock Form
Be able to go through a series of Conversion to build a Quiz/Survey type Conversion.
Add possibility of using a countdown timer on the Conversion block.
Add ability to split test mulitple Conversions to see which one converts the best and then use that one automatically after a certain period of testing.
Documentation is missing about which email marketing tools Conversion can integrate with. And how to go about integrating with them.
Update the analytics to show the daily conversion rate as well as over a period of time
An option to add a conversion inside a page or post, for example, after the first paragraph would be a nice way to show inline ads or conversion items and be able to track conversion rate.