Evenito has no influence on the spam quality of the emails.
However, there are a few tricks you can follow to make sure that the messages reach their destination better. For example, it helps if you write the links in the mails full with "https" initially. Also all links should work, so no "dead links" leading to outdated sites or into space.
To test the quality of the emails, there is this useful tool: https://www.mail-tester.com. Here you can send your test email to the address given on the start page. After about 30 seconds, click on the "Test" button. Then the email will be analyzed and you will see what you could do better in the email.
It can also happen that when sending test mails to your address, the messages are blocked by a filter of your organization and therefore do not reach your inbox. In this case it is best to test the sending on a private email address. If this works, you can ask your IT department if a special filter has been set up.