@hotbit's proposal has some assumptions about GRC exchange rates that I think are overly optimistic.
I'm not sure is a tax system is best, but either way, it would not exist in time for a 2018 budget.
Dumping 20% of the foundation wallet into payments every year would destroy GRC value.
Developers full-time compensation, rather than hourly, is very premature, and would squander funds.
I like that we are having budget discussions, but I think we can be a little lighter, and a little less rigid.