I don't think that all of the increased lifespan is due to healthcare spending. Various enviromental regulation likely increased lifespan. Our current paradigm of drug development unfortunately get's exponentially more expensive via Eroom's law. I doubt that simply spending more money in the same way produces linear progress.

I think the problem of the mythical man month also exists in research. You can't simply throw in more money. Given researchers money can often make them spend money on fancy equipment instead of thinking hard about what to do.

As far as hopes for the future of biology goes, I hope that Theranos will introduce something like Moore's law into blood testing prices. If it succeeds with that mission it's not simply because there a lot of money thrown into blood testing but because Theranos focus on producing cheap blood testing while currently the companies in the market have no incentives to test cheaply.

YCombinators turn to fund biotech companies also fills me with hope. Bikanta Nanodiamond technology that allows very high resultion imaging of anything that you can hit with an antibody fills me with hope. The promise 100X more precise cancer imaging but if their technology really works and the can do it cheap, it has application beyond just cancer because being able to image anything at high resolution will allow us to learn to tag a lot of different things with antibodies. You could tag drugs with the nanodiamonds to see where in the body the drug travels.

The fact that nanodiamonds are a solution also suggests that simply moving all research dollars to biology would be bad because nanodiamonds needed a lot of physics research to become viable. Better signal processing algorithms and AI might also further increase the precision of their imaging.

Another great biotech company founded by YCombinator is uBiome. Thanks to relatively cheap DNA sequencing they track bacteria population on skin/mouth/gut/nose and penis/vagina. At present sequencing prices their technology isn't mass market compatible but if sequencing prices continue to drop at rates of Moore's law or faster than Moore's law we will have a new area of medicine. In 20 years we might all consciously repopulate our bacteria populations.