I really don't know how the rental pricing structure degenerated into a resell/phantom pricing structure discussion but here is my opinion.
I think the current price structure that we have for PS4 games 35/25 is just the right one for $60 games it looks for me fair for both the reseller and the phantom, for me buying a phantom for $25 it's just fair, not cheap but fair, especially if you plan to keep the game, in my case I like to have a big library of games to choose from, I personally don't buy PS4 phantoms because I have no space on my PS4 (bought a huge phantom when I got the console and no one told be to buy a 2TB HDD from starts) if I had the option I would pull a Snakey and buy only phantoms, I did with my PS3 and really enjoy taking my time to play and enjoy all the games on my library.
The main problem that I see with Resells it that they devaluate extremely fast, man! is like buying a new car you pull it of the dealership and right there you lost 30% of the value, so if I buy a game for $35 and plan to sell it three weeks later, I would only get $25-$30 for that (I saw that SoM and A:Iso resells for $25) so you are basically paying $5-10 for a three week rental and you have to face the full value of the game, but even though you have this devaluation people still find the $35 fair and attractive.
Using a 40/20 price structure for a $60 game would be really attractive for the phantoms but not so much for the resells, the thread would be flooding with people looking for PS4 phantoms and no one willing to pay $40 for a resell, why would anyone pay $40 for a digital resell if they can get most of the games preordered from dell with a $25 giftcad after the first $60 you would pay $35 for every game, yes they come a week later but then you can just take your game to bestbuy when they have some promotion and get your money back, and on top on that the resell market would be so limited that it would get really hard to sell that some weeks later.
We can clearly see that people is comfortable with the price structure seeing games like CoD:AW, see how many people is looking to buy PS4 phantoms even if everyone would have used the $18/12 structure there would be just as many members looking for phantoms. the main problem is not the price, is that we are looking to get the games as cheaper as we can but in the specific situation of the game sharing scene the cheaper one gets it the more expensive is for the other.
P.S. I think, like Raiborg said before, that a different price structure should be used for games that are $40 or lower.
P.P.S. I also think that a $5/week rental is insane, but like everyone before me said, it's a free market and if they find someone willing to pay that then go ahead but if I see the same game that is being rented for $1.5 - 2.0 by an other member guess what would anyone would choose.
A rental for $1.5 -2.5 is just fair and I don't see it as a way to profit I see it as a way to get some money back for the games that you are not using at the moment.
EDIT: and Snakey I would take that phantom for $30 in a heartbeat if I had the HDD space!