Well, I never said I was a Libertarian "idealist"
I also support a reasonable degree of anti-trust laws. Regarding open sourcing of software, all it takes is someone to say "give me the source so I can compile it myself" and they either get it or they don't. This doesn't require active government regulation. If someone wants the source and it's not available and won't be given to you, then you notify the government and it's quite clear-cut - either they will give it or they won't. Not doing so would be illegal. No loopholes, just nice and simple. If no one calls out a person who doesn't make the source available, more power to that person, and here's to hoping they never become successful.
Overall, in terms of regulation, what I'm proposing would be a drastic reduction. The contols granted in copyright would be returned to the VERY minimal controls of over 100 years ago, covering only publishing and only being applicable for 14 years. Software would need to have a seperate section, since it progresses so quickly, in which copyright length is restricted to, say, 5-7 years. Patents would be minimized and the USPTO would be completely overhauled. Again, a return to 100+ years ago would be beneficial. Again, this would be less government regulation as opposed to more. And the resulting regulation would be quite minimal and clear-cut. It's a simple question of yes or no - either the source is available or it's not.