Hi Carl-my thinking is that the cost should (other than for the first year of the rule implementation) be exactly the same, since purchases are limited to one new chute per year (regardless of weight). And having two chutes availbale might even extend the usable life of both chutes, since the half would rarely be deployed in conditions where it would be under stress, and the 3/4 would get significantly less use and would not get in situations where it is hanging/chafing against rigging when wind is near 0...
As one who sailed with somewhat tired sails at my last NA's (and for the last three seasons) for financial reasons, I understand the concern over cost of upkeep. But I really think this shouldn't have much of an impact.
