Great motivations behind migrating to GCP to take advantage cost, MySQL and privacy.
Why would not you chose other dev-friendly players like DigitalOcean, Exoscale? Are there rationale behind not adopting multi-cloud?
I would have suggested (magic.cloudureka.com/#!/compare) to help you measure your ROI from AWS to GCP (and other cloud options), even before the migration.
Disclaimer: I'm one of the founder of Cloudureka.
We considered other options, however managed MySQL and encrypted network traffic/data at rest are two things that we value and that are not provided by most of them out of the box.
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.