I still wouldn't be putting the pen through Penrith. I agree with most of the sentiments above, but even in spite of their performance last night, I think Penrith have the most upside of everybody else outside of that proposed top 3.
I think that Penrith would not exactly be a team fighting it out for a minor premiership. They are more likely to be a threat come finals. The Chooks and Storm are vulnerable to a bit of fatigue, and the Roosters will have teams try to ambush them every week of the regular season (like any defending premier has to experience). The Storm will probably show more signs of missing Slater when they are in the biggest games, and an older Smith without his mates in Cronk and Slater might not be the Smith of old.