You can always improve on something, the technology is different today, but I would leave it well alone. If there was something that was incomplete, that might be interesting... because I do that on my website. ↗
Technology causes problems as well as solves problems. Nobody has figured out a way to ensure that, as of tomorrow, technology won't create problems. Technology simply means increased power, which is why we have the global problems we face today. ↗
An international race in the relevant technologies is getting under way at this point, not necessarily with an understanding of where that race leads in the long run, but strongly motivated by the short-term payoffs. ↗
My greatest concern is that the emergence of this technology without the appropriate public attention and international controls could lead to an unstable arms race. ↗
Protein engineering is a technology of molecular machines - of molecular machines that are part of replicators - and so it comes from an area that already raises some of the issues that nanotechnology will raise. ↗