This is a great analysis. I think UBI is going to be a deathly serious subject in the next decade and it's frustrating to see lots of half-baked reasons why it doesn't work - especially when there are studies going on all around the world.
And it's not just UBI-specific studies. Giving a poor person $10,000 is going to stimulate the economy in the short term more than giving it to a rich person - the poor person will likely spend it on goods and services, so the money goes right back into the system. A rich person will invest or save it as it does little to improve their already adequate cash flow.
At the end of the day UBI isn't about wealth redistribution. It's about sustaining economic growth. I believe a rising tide lifts all boats - that is, a growing economy is good for EVERYBODY. In this sense, UBI is an economic problem, not a welfare one.
RE: Universal Basic Income Profitable? - Yes!