But why do you assume that I am "setting myself up to get paid way less"? As I said, I have no evidence to suggest that I would command a significantly higher rate on a daily or weekly basis than I do now. However, not taking on any gigs that aren't really full time (but can be combined at my discretion with others that also aren't) would certainly have cost me money in the past.

I can see the argument for fixed price vs. T&M billing. I guess I just don't see why going as far as daily/weekly billing doesn't net a significant part of the downside (no hard limit on hours vs. compensation, no clear cut-off where clients have no claim on any work I do other than for their project) without necessarily netting much upside.

As I said, perhaps that's the way the game happens to be played in whatever markets you've been working in. I'm certainly not saying you're wrong about your own situation. I'm just suggesting that your comments here are black-and-white but don't necessarily apply to everyone else's situations as well.