A few things that come to mind reading this.
What would give the inflation value over time as it grows, that would keep it from eroding the spending power of the recipients? We already see this issue under the current capitalist models that benefit the bankers and their constituents. I get that an asset based currency lacks necessary elasticity for economic growth, so where is the solution?
I read years ago a response to extremely rich folks on the left complaining about low taxes for the rich. It was along the lines of no one is stopping them from adding zeros onto their taxes, or stopping them from being more charitable. The truth this seems to expose is that it's not in most wealthy peoples hearts to be charitable except for virtue signaling and to toss some crumbs. It has me wondering what would protect those on the basic income from having schemes developed to defray the value of their monthly stipend to force them back into working for the wealth holders dreams? Man's capacity and desire to multiply their own wealth at the expense of their neighbors seems to be the stories of history, and not sure how this idea would be immune to this dynamic.
Some of those on the basic income would be jealous and hateful towards those who apply themselves for more, coveting what they have as they insist the results of the extra expenditure of energy and talent were unfair.
It seems there is an unfairness from both sides of the class equation, and no matter how you would draw up distributions there would always be those unhappy with their share demanding more than what is probably fair.
Seems people will have their issues regardless of the system implemented.