Save 50% on a Google Pixel 3 or Pixel 3 XL
https://www.cnet.com/news/save-50-on-a-google-pixel-3-or-pixel-3-xl/
Everything you need to know about these phones can be found in CNET's Google Pixel 3 review and Pixel 3 XL review. Verdict: They're both awesome, though the lack of expandable memory is a bummer. If 64GB isn't enough for you, consider spending an extra $50 (on either model) to jump up to 128GB.
As for Google Fi, it's not the cheapest option out there: For $20 per month you get unlimited minutes and messages, while data runs $10 per gigabyte. However, you pay only for what you use.