I agree that the low man on the totem pole bears the greatest degree of risk. Consequently, the abstractors should price their services accordingly.
In addition to the escalating costs and expenses of performing the search the risk involved requires proper remuneration of the abstractors. The abstractor's pricing problems are largely the result of their having allowed themselves to be beaten into submission by the VM's. They have reduced their fees out of fear of losing existing business to low ball competitors or in the alternative in the hope of attracting higher volume which the VM's promise, but which may never materialize.

Some states do permit disclaiming liabilty for negligence. Connecticut is not one of them. You can limit liabilty in Connecticut to a reasonable amount (possibly the cost of the search as you suggest). However,  limiting the amount of liabilty  requires an agreement preferably in writing which memorializes the intent of the parties to the limitation. In Connecticut it is not enough to just draft that limitation into the title abstract in an attempt to unilatterally impose the limitation on the other party. 

In so far as claims management is concerned, the title insurer does in fact honor its RESPA obligations when it pays a just claim. The title insurer then seeks recovery of the pay out from the abstractor for his having produced a defective abstract. Very often there are subrogation clauses in the title insurance policy which allow the title insurance company to stand in the shoes of the property owner for recovery of damages. If the abstractor was negligent, he is indeed liable for the full measure of damages which are proximately caused by his negligence.

The abstractor then offsets the title insurer's claim by notifying his e&o insurance carrier. The boiler plate language of his e&o policy usually requires that the litigation be handled by the law firm of the e&o insurer's choice and that the costs of litigation be deducted from the proceeds of the e&o insurance, thereby further reducing the funds available to pay the claim. If the abstractor was in fact negligent, the claims process has been properly handled. As far as I know RESPA governs the redition of core services among the various parties to a real estate transaction. The recovery of damages for negligence or contract breach is governed by the laws of the state in which recovery is sought. The recovery claims arise from violations of statutory and common law rather than through RESPA.

The problem may arise that the e&o insurer may opt for resolving the case as cheaply as possible. This means settlement of the claim without trial. In which case the non-negligent abstractor does not get his day in court to prove that he was not negligent, but his premiums may increase or his coverage may be cancelled because of the claim. READ your e&o policy carefully before renewing it.

The reason your e&o coverage increases every year even though you have not filed a claim is because the e&o insurance carrier is covering you for a longer period of time than under the last renewal. Is it fair? Who knows. No one ever said life had to be fair. It is the condition imposed by the e&o insurer for renewal. You have the option of seeking a less expensive premium from one of their competitors.

Your laws may differ in Florida, but the above information is how the claims process is handled in Connecticut.