Cool idea! FYI: There IS Universal Basic Income via Cryptocurrency!
The thing is that UBI via government could never work because it would eventually only cause inflation which would cancel it out in a few years, unless only some got UBI while others did not, but that would defeat the purpose because it would continue our systemic inequality.
I think this is because government has no money of its own other than our own tax dollars.
However, UBI via Crypto could work because it's supported by all of us, especially those buying it at a later date.
Check out these two UBI coins:
MannaBase: https://www.mannabase.com/ (You get free 100 Manna week!)
SwiftDemand: https://www.swiftdemand.com/?referred_by=kundanchhabra (You get 100 Swift a week + 500 per referral. And yes, this is my referral link which I hope you use because it will get me an extra 500 Swift). Swift is technically not crypto yet but has plans to go crypto in mid-2018. However, you can use the Swift currency to trade actual good and services on their site.
Simbi: https://simbi.com/kundan-chhabra/welcome (This is more like a digital time bank. I believe you earn 75 Simbi just for joining and then 25 Simbi per referral. You can then trade services on Simbi OR pay/be paid in Simbi).
Also see my related follow-up article to this on Complementary Alternative Currency Systems:
RE: Pay Your Teachers, Artists and Writers: 7 Types of Unrecognized Labor that Need to be Recognized