I just found this comment from Walter Bright on a previous thread on this topic. I think it's brilliant:

Loser pays can work when the amount the loser is liable for is the minimum of his legal fees or his opponent's legal fees. That puts the maximum he is liable for under his own control.

I love this idea, as it completely prevents the scenario where a well-financed plaintiff uses the most expensive lawyers and runs up a huge bill, just to add to the defendant's risk and encourage a premature settlement. Under this rule, if you want to spend a bunch of money on good lawyers to improve your chances of winning the case at all, go ahead, but you won't collect more in fees by doing it, unless your opponent does the same (as they presumably will if they can afford to).