Dynamis is just fine the way it is. Its expensive enough to keep everyone and their mom from cock blocking time slots. And its cheap enough to pay for itself in one way or another. Seriously, if your not doing zones @ cost, your doing something wrong. Id argue that the problem is not on SE's side, its on your side.
I've been running or helped run the same Dynamis aspect of my LS for years now and at the moment we are doing a near perfect job of breaking even at costs, and keeping requested AF rolling in. All zones, including CoP zones are in our agenda. The only loss zones (in terms of gil) are CoP zones. The drop rates on our win runs have been more then excellent, so it justifies the loss. On runs with currency (Cities and Beuc) or system not only pays for themselves, but makes enough profit to pay for the CoP runs.
All this coupled with proper zone planning you can create a break even/profit dynamis system. All that you have to worry about then is zone efficiency. You need to have a solid group with a 95% win ratio to make a good system win. So if you keep losing zones, or keep wiping on farm attempts, then its an issue of your strategy/play skill. Then you need to reevaluate the way you play, not how SE handles dynamis.
I dont mean to sound like an ass by saying this, but lowering the dynamis cost would hurt the more experienced dynamis shells. The shells that have 0 problems with wins/paying for runs/drops. This may sound egotistically but I do not have any major problems with the way my dynamis leg of my shell is run. (Other then me slackin on point updates, but that will be taken care of soon

) That said, the ONLY thing that can hurt me is MORE dynamis shells popping out of no where and stepping on my time slots.