Thanks guys.
If anyone has questions about when characters are out, make sure you ask the CMs in black Star Wars shirts. The other CMs with the characters (they are in white and blue stripes) don't know as much (most don't even usually work on DHS, they are brought in just for the event.) The right CMs always were able to tell me when a character would be back out, while the others either said they didn't know, or, I think made things up (one told me Anakin wouldn't be back for an hour and a half. I asked the black shirt CM, and he told me 4:50, which was about 30 minutes from when I asked.)
I was lucky enough that I never had a problem trying to catch a character in the lines where they switch out. The only time I got to the front and wanted a different character was for Kit Fisto, and they let us wait (there were about 3 of us waiting.) And then we lucked out and he was with Shaak Ti when I got up there.

From what I could see, the CMs by the Fetts and in the tent (for the droids & Luke & Leia) were the ones that wouldn't let you wait, but the CMs obviously may change over the course of the weekends.
For the fab 4, I went straight there on the first day. Got Mickey, got back in line, caught Minnie, got back in line thinking it would be Donald...but it was Mickey again. The black shirt CM told me the next time he would be out, so I was able to use my TSM FP (I didn't think I'd have time to ride TSM at all during SWW, but I was able to ride 6 times over 2 days! Not bad!) Got back to the line and just missed Donald, BUT, the CM told me Donald would be out briefly with Goofy right before they left for the parade at 11:40, but the line would be closed soon. So I just got back in line (the line was closed a few people after me), and was able to catch them together (I heard they didn't do this the next day, though, so I'd double check with the CM if you're trying to get them together.) So basically, the first half of the first day was just getting those 4 characters. I was glad to never have to stand in that line again, lol. Even at 10am that line was brutally hot since the sun is RIGHT on you. I never thought I'd be able to meet a lot more that day, but all of the other lines went much more smoothly.
Forgot to post about one of the cool celeb moments I had! I didn't go to meet any of them, even though all but Ray always had spots available when I got to the park Friday & Sunday (Saturday I got there late, just to see the parade, though I still met a few characters.

) But thanks to this thread, I knew I could go around and take pics of the celebs. I did this for Ray one day, and then went back on the last day. Dee Bradley Baker was just leaving, so I went to snap a pic on my phone (I was tweeting pics all weekend

) & he said, "wait!", took my phone, switched it so it took a front picture & took a pic of us together!! I kept saying thank you! I was pretty excited
Everyone signs except C3PO & R2D2. Not all of the Catina Band members sign. I caught one that didn't, he motioned that another one did, but I didn't feel like trying to grab him to get an autograph...catching the roaming characters can be a pain, and I was just happy to get a pic with one, lol. Aurra Sing is awesome, but a pain to try to get to stop and get a pic or sign. After following her around for a bit, and trying not to smile at her, she finally stopped for a second so I could get a picture. She wouldn't sign my book, though.

She did grab some books from others, so she *does* sign, it's just hard to grab.
BTW, if you ask one of the black shirt CMs in that area, they will know exactly when the roaming characters come out as well. That's how I was able to catch the last 2 I was trying to find.