One big disadvantage is that you won't be interacting with other researchers from whom you can learn.
Research seems to be an insiders' game. You only ever really see the current state of research in informal settings like seminars and lab visits. Conference papers and journal articles tend to give strange, skewed, out-of-context projections of what's really going on, and books summarise important findings long after the fact.
At the same time however, you might be able to interact with researchers more effectively. For example, you could spend some of those research weeks visiting selected labs and seminars and finding out what's up. It's true that this would force you to be conscientious about opportunities and networking, but that's not necessarily a bad thing. Networks formed with a very distinct purpose are probably going to outperform those that form more accidentally. You wouldn't be as tied down as other researchers, which could give you an edge in getting the ideas and ...
Ideally, I'd like to save the world. One way to do that involves contributing academic research, which raises the question of what's the most effective way of doing that.
The traditional wisdom says if you want to do research, you should get a job in a university. But for the most part the system seems to be set up so that you first spend a long time working for someone else and research their ideas, after which you can lead your own group, but then most of your time will be spent on applying for grants and other administrative trivia rather than actually researching the interesting stuff. Also, in Finland at least, all professors need to also spend time doing teaching, so that's another time sink.
I suspect I would have more time to actually dedicate on research, and I could get doing it quicker, if I took a part-time job and did the research in my spare time. E.g. the recommended rates for a freelance journalist in Finland would allow me to spend a week each month doing work and three weeks doing research, of course assuming that I can pull off the freelance journalism part.
What (dis)advantages does this have compared to the traditional model?
Some advantages:
Some disadvantages:
EDIT: Note that while I certainly do appreciate comments specific to my situation, I posted this over at LW and not Discussion because I was hoping the discussion would also be useful for others who might be considering an academic path. So feel free to also provide commentary that's US-specific, say.