TricepMail is designed specifically for privacy, and not only privacy for your data on TricepMail’s servers but for preventing others from tracking and selling your information as well. The privacy policy specifically states that there is no collection of your personal information. TricepMail is based out of Colorado, US, but considering moving to another country which might be better for privacy.
The UI is definitely very minimal, but that is on purpose by design. No need for a bunch of visual clutter when reading/sending email. Improvements can and will be made though, of course.
I could promise you I'll send you a legit authentic fancy gold Rolex worth $20,000 if you transfer me $15,000, so you can re-sell it and make $5,000 in an instant. Would you believe me?