I agree, changing the rules too often does not help with cost-cutting at all. Anybody knows the retooling costs are really high for any type of production, be it a road car or an F1 car. Changing designs costs money, period.
But, that does not mean the rules shouldn't change, they just shouldn't change as often.
BTW, I believe a fuel spec would be a great idea and could really highlight some creative engineering, after all, you cannot treat anything as an infinite resource because that's just not reality. we should encourage engineering that can be applied to real-world situations. F1 has become a completely corporate meta-technology land. It'll be a long time before a pneumatic valvetrain appears in a production car, but it's been in F1 for how long, 10+ years. Ideally, we should be seeing F1 tech on the road within 5 years. Can you imagine how this could transform public perception of the sport. People might be more interested to learn about F1 tech because they know it'll end up in their road car, instead of the other way around.
I know I buy Bridgestone tyres only because I believe their F1 tech ends up in the design (potenza reXXX only). I would think it would be hard for a tyre manufacturer to not improve their designs directly from racing, esp. in F1. But I think that's peculiar to tyre making.
Whereas, Honda or Toyota have so many different cars, it's hard to say that ANY of the F1 tech ends up influencing the design (although, we soon shall see the first Honda V10 road car). But Toyota, c'mon, you'd hardly know they're racing from their cars, so boring, every one of them. I have yet to figure out why Toyota spend soooo much money on the sport, for what rewards do they reap?
I love to love Senna.