First of all the idea is good but there are some other better biometric security way like Iris scanner that recently is introduced on the Samsung Note 7. I don't know if you know but the fingerprint can easily be hacked by some kids toys that use in kindergarten for more check this video how can an iPhone touchID can be hacked/tricked: http://www.dailymail.co.uk/sciencetech/article-3471718/Can-iPhone-s-fingerprint-sensor-hacked-using-PLAY-DOH-Researchers-claim-toy-bypass-Apple-s-security.html#v-5041464962111065112
This was what I was referring to back in the 1st page... To be able to replicate a fingerprint this way, you have to have it very beautifully "printed" on a surface, and that doesn't happen frequently in real life
At least we can count that this method does it job and fingerprint is not secure at all, it is needed online one time and all bitcoins can be lost, I haven't made a deep research but I believe that there are more ways to hack the fingerprint but maybe an Iris scanner and a password or/and a 2FA would be enough.