The answer to that question is that the top two remain the top two with Written Tycoon and I am Invincible still ahead of their more expensive rivals.
Below is the Sire Profitability table sorted by straight profit (Top 20) and as you can see it brings in a lot of the more expensive sires that might not have the flashy multiple of service fee of a cheaper sire, but nevertheless deliver plenty of cold hard cash to their supporters.