I got to disagree here since all frequencies reduce at the square of the distance - once you get down in the woods - might be that no one will be able to hear you.
Your points are all valid. However, around these parts there are usually loggers nearby, and log trucks in and out. Those guys use CB for communications among themselves, so chances are very good someone will hear me from the logging site, or else a truck will come within range. I do plan on using a good antenna and boosting my signal as much as I can afford to, though.
If I get stranded there's a good chance I will be up high, since I mostly go out there to take my telescope and stargaze. Some of those places, you can see for 20 -30 + miles on a good day. That should help get a signal out.
Still, getting a ham license isn't at all a bad idea. In fact, I really, really want to get one. Money is a large factor right now, though. If I could get talking HAM for $2-300 I would be all over it. But entry level mobiles seem to cost upwards of $1000 +. Way, way more expensive that a $150 CB.
Anyway, the CB is basically just an added layer of security. Sure, there's a chance no one will hear me. But in my situation there's a good chance someone will, too, and that makes it worth it.
If all else fails, I always carry emergency gear and tell people where I am going, so I can camp out in the back of the Jeep until someone comes by or comes looking. Shouldn't have to wait more than a couple weeks.