yeah, i was kinda expecting the Anaking falling 'into' the lava thing and obi-wan thinking he was dead. at least at the time he left him. would explain why he didnt finish him off and/or save him.
as far as not trying to turn Anakin back to the light side, remember, even if ESB Yoda (so i would assume all the Jedi) assumed that once you went dark 'forever will it control your destiny'. It wasnt until Luke that anyone thought you can be turned back to the light.
I almost think that Yoda shouldnt have had a cane at all. That (maybe) should have been something he developed while on Dagobah, or maybe from his fight with Palps. Also, they did seem to force the 'Yoda talk' in the PT's making it seem unnatural. After watching the OT (mainly ESB cause he has the most dialogue there) he really doesnt speak all that abnormally while training/explaining things to Luke. The majority of his 'crazy' talk comes when he first approaches Luke and is testing him, when he's just acting like some crazy creature to test Luke's patience (also he probably went a little nuts from being on Dagobah all alone for so long) So that could almost have been a developed thing like the cane.
Kind of agree with the battle droid comment, yeah, they shouldnt really present much of a challenge for a Jedi, but it probably could have been a bit harder for them. Also, the Jedi definatly got wiped out by the Clones too easy. I mean the clones back up and let the Jedi get in front, then shoot them in the back and the Jedi didnt notice. Even non force adept people would turn to look when the speeders on your right and left fall back. And only like 2 of them actually put up any sort of fight, besides Yoda.
-Darth Simon