I don't see the point to making your hours essentially random. If you want to work more, make another or a bigger proposal.

My preference at this point will be to vote for proposals that use the @good-karma script (or equivalent). I don't really see it as "proposal costs 0", although it might happen to be that at a particular HBD price. It is more like just a way of sending back the any funding above what is needed to complete the proposal, and doing so precisely at the times (higher HBD price) when stakeholders and HBD can most benefit from that funding going to @hbdstabilizer (or the equivalent).

@blocktrades has elsewhere stated his views that the benefits of buying HIVE and channeling that into the DHF fund are too great at high HBD prices to forgo, but the script normalizes this a lot by sending back in those times when the price is higher.