I wouldn't encourage the chewing behavior in a puppy... you could spritz her tail with bitter apple spray once, and see if that discourages it! She should also have tons of safe chewies to keep her distracted.

As far as Gonzo, he didn't grow too quickly. At about 5-6 months, they hit a gawky leggy stage which is very cute! They're usually (ideally) very lean until 1 year, when they start to fill out. You should keep her nice and lean (you should be able to feel her ribs, not protruding but with a thin fat covering) because slow, steady growth is much more healthy for her! ^^ Also, we definitely need adorable Cali pics!