Yup thats right the little green dude isn't a very good general. Something about the battle on Kashyyyk has always bugged me in the way that it is shown. And no I'm not talking about how much of the battle we see (although I wouldn't have minded seeing more ) what I'm talking about is the 'order' in battle itself. First off the Republic seems to have next to zero organization. Granted I know that they were quickly sent there but everything seems to be in shambles on the beach. There is NO defensive line, the Republic should have had a strong primary line along with a few backup lines. There is next to none of that, there is one small trench but only a few clones are in there and I don't think any Wookies are in their at all. Again there isn't time to set up an "Atlantic Wall" as the Nazi's did during World War II but something would have been better then what the Repulic had. Even the smallest bit of protection is better then no protection at all.
Secondly where was the artillary? I only saw one piece that was left out in the open and quickly destroyed. Next: why were the Wookies allowed to run out and 'meet' the incoming droids? They should have kept cover allowing the enemy to come to them and to wait until they had a firing solution. Running out to meet the droids in the open would only increase casualities. Also why does Yoda have so many clones taking pot shots from the tree's??? Small arms fire from such a distance isn't likely going to do much good, up in those tree's might have been a good place to put some of the heavy guns... although they don't seem to have any. And lastly you can see in the background the Star Destroyer that the clones came to Kashyyyk in, this should have been much farther back. If the droids break through the Repulic's lines they could easily get to their ship. Even if the line is only breached by a small number it wouldn't take much to put the ship in real danger. The ship should have been WELL behind the lines inorder to maintain its saftey.
I'm sure nobody else has thought about this but I've been involved in reenacting and have studied military tactics so I'd like to think I know a few things on the subject.