What I would prefer is a discounted lump sum paid out to IP owners, at the time of patent filing/copyright. For instance, instead of having to legally defend a medical patent for 20 years and overcharge hospitals/distributors during that time, receive a discounted cash flow equal to the approximate amount of value that would be forgone by pricing the innovation at competitive prices.
Of course this system isn't foolproof, and would be subject to tremendous "gaming" from patent holders and regulators, but innovators could reap the rewards of their innovative research without having to deal with pricing their products out of reach for some individuals who can't afford the price.
Again, it isn't foolproof. But there exists a "most efficient" means of balancing the risk/reward of innovation that lies somewhere between "IP rights should be forever" and "No IP at all."