Rotschild&Stiglitz (RS) Equilibrium
It is important to remember that figures are not proofs. Minor mistakes in the figure are hard to detect but can change the outcome. Algebra is much more reliable. 

Right now in your figure the low risk type consumers have indifference curves that are upward sloping somewhere. It seems though that is not critical here. 

The visualisation of subsidies seems to be the bigger issue.  You need G and H to be the same distance away from their respective original zero profit lines. Thus the 'new' isoprofit lines should run parallel to the old ones, and at the exact same distance.

It seems to me that it is impossible to place GH on these lines while preserving incentive compatibility because of the relative slopes. However, this is also not proof. If you outline an exact GH pair and type up the equations that you think show that they constitute an improvement while being incentive compatible, you may get better answers (as well as a better understanding of the model).

EDIT

It seems to me, that in your numerical example the subsidies do not cancel each other out. It is not enough to change the rates by the same percentage, because the different types do not buy the same amount of insurance.

It costs $8\% \cdot 90 = 7.2$ to subsidize the high risk types, but only $8\% \cdot 15.4242 \approx 2.78$ is collected from additional fees on the low risk types. If there are the same number of people in both types, this will not work. But it seems to work if there are for example three times as many low risk people. I actually find this very surprising. I checked both IC constraints and all the utilities, and everything seems to check out. 

Your new offers will definitely not be an equilibrium though. As long as one insurer offers the high risk insurance, other insurers can offer just the low risk one. With no high risk customers to subsidize, they will make a profit. By moving the high risk offer a bit more to the right they can siphon off all the low risk consumers from the cross-subsidizing insurance company, who will then suffer losses. So I guess the RS equilibrium is a kind of long run equilibrium.