google has 400+ recommendations (specs, recommendations, posts) about what you have to do to perform well in google. without even counting schema.org or other initiatives.

(google) analytics is an unbelievable powerful tool that has at some companies whole teams dedicated to it

google webmaster tools is a unbelievable powerful tool that tells you 80% of everything that is wrong with your site. you can easily make it your half time job to use this tool to the fullest.

google is part of the triangle: your webproperty, the users, google search

your ressources are better invested into these three areas (analytics, webmaster tools, google recommendations) than in a third party with its own interest i.e.: selling tools