We're considering getting listed / joining the AWS Marketplace. What are a few of the best reasons to sell our software through the AWS Partner Network?

There is a lot to this answer, and better articulated via the AWS website: https://aws.amazon.com/marketplace. In a nutshell, if your solution runs on AWS, then AWSMP is a fantastic route to reach AWS customers and participate in co-selling by leveraging the wide ranging solutions and resources of AWS.