I love looking up TB pedigrees. :) My OTTB has pretty decent lines too--Northern Dancer, Grand Slam (so also Gone West, Mr. Prospector, and Secretariat), and Key to the Mint to name a few. Even though some of them are incredibly common, it's still exciting to see famous names in there!
Secretariat is generally in quite a bit of TBs pedigree..He just sired so many offspring that it's hard to get away from that line..
Your mare is very cute..She definitely has Secretariat in her pedigree and a few other bigger named horses. Even if they are farther back they usually lay a nice foundation to set up for a good horse. I don't count out the bigger names farther in the pedigree, I just like to see the bigger names closer as well.. You did well getting her as a rescue with those lines..
It's always cool to have a horse related to a famous horse. Wether they're distant cousins or grandsons. I have a Paint yearling who is distant cousins with all but either 2 or 3 of the Triple Crown winners!