I'm all for simplicity and efficiency. However, the primary goal should be meeting basic needs, not cutting government. If UBI is to replace social programs, it must provide enough of an income to make up for the services cut.

Housing costs are sky rocketing, as one example. Without housing subsidies, a $1000/month basic income is not going to be sufficient for many. Universal health care will also be a necessity as it would be impossible to afford health insurance on most of the UBI plans I've seen put forward.