Chatter bait come in many different sizes, small and even what you might call excessively large. You need to match the size of the chatter not just to the size of the fish, but to the size what the fish are eating. If they're going after bigger targets, get a bigger bait. Don't make it too much smaller than available bait fish in those waters, of the bass will just go for something bigger. Make it too large and they won't even try to bite.
Cold waters and restricted spaces can lead to limited growth, so use a smaller chatter bait if you think you're in those conditions. Warm and expansive waters should correspond, to some extent, with larger chatter baits.
My basic size is a 3/8 ounce on a 17# line. It's great for shallow-water situations. When fish are active I might push it to a 1/4 ounce size because I can create a more natural, erratic action with it. I prefer the original blade size all the time even if I do change the head weight.
Next time, I'll explain my color preferences.