You could quite easily swap Lambert and Rod around in the 4231 formation, infact there are a lot of options available to us. Lambert, Rod and Sharp can all play up front, you could also have Guly, Lallana, Puncheon or Lee in the hole. Puncheon, De Ridder and Chaplow can play out wide. Cork can play the holding role too.
I agree with your second point entirely. I don't think we're good enough yet, we need 3 players in at least. Will we get any before Man City? It's looking unlikely.