I would really like to see a real world UBI experiment. For example, implement UBI on two small communities. To counter act the impacts of potential inflation the experiment would need to occur for about 5 years because inflation follows changes to cash flow with a tail of about 9 to 12 months. You would need two communities to test whether isolation has an effect such that one community is geographically isolated from other population centers and the other is a suburb of a major metropolitan area.

I suspect there are all kinds of interesting pros and cons worth study, but without trials everything is just a wild guess.