Curious about the referrals... I plan to write a couple articles about your site on my crypto blog and maybe make a video for you... hoping those pay off for you AND me (of course!) with lots of sign-ups.  But I also wanted to check on something.  I referred my roommate, but I didn't get credit for a sign-up.  I will make the assumption that it's because it's showing up that the sign-up came from the same IP address -- but I figured I would check to be sure.  And even though my referral was legitimate, if you aren't blocking or guarding against multiple accounts from a single IP, you may want to consider implementing such a system so someone doesn't cheat the system.  I'd hate to send 50+ referrals your way and lose out to some schmuck who "refers" several hundred virtual machines or sandboxed browsers to steal your generous .2BTC offer.

P.S. You're welcome for the user interface tip.