Extend the package to use google APi for sending emails 

Instead of plain SMTP connections to google mail server 
which depend of the availability of "less secure apps" turned OFF 

maybe create a second package (dot-mail-google ? ) , or extend this one , to use google API client 
API keys, 
token, 
in order to assure deliverability of emails 

https://github.com/googleapis/google-api-php-client