Excellent thread. I've seen a lot of posts with people listing a line full of premiums, and while that is great, it isn't really much use if the other lines are full of rookies. Looking at it this way is another good way to look at our sides.
It is a difficult question to answer, because I haven't finalised my trades, and as others have said, we have non-rookies who might need an upgrade.
Before trading this week, I have 7 rookies on field, which will most likely become 6 after I trade.