Personally, I'd prefer that more work was done, then funded, when possible.
Thank you. Paying for work already done as apposed to funding something that may not deliver (the final say so could well be out of the hands of the worker e.g. Exchange listings) make far more sense to me.
I'll do the work for free and if I deliver, pay me, and if I don't, I don't get paid
Who wouldn't opt for this as a business if they could!?