It seems a bit odd that people in the control group also got $50/month, while the treatment group received $1000/month. I would be interested in a slightly different experiment:

* Make multiple treatment groups; for example in which individuals would receive $1000/month, $200/month, and $50/month each, respectively.

* somehow create a control group who would not receive anything. Yes, it would be tough, but it seems important.

* Get participants from (say) the lowest income decile. Or at least be very careful to note the pre-treatment income of participants and their family, then correlate the results with the pre-treatment income.

The goal would be to understand the benefit-versus-amount tradeoff. Further, are there significant benefits that come from $50/month? If there are, then it would be much easier to fund. I don't think policy peeps should shy away from such less ambitious projects, even if it isn't called an "income"