Crash , I didn’t any the same as you, so obviously I am not understanding the rules and I’ve changed them around for my understanding.
With the metro I was only looking at races from 1200m up, Also think 3rd race in from a spell, is a good change.
This is the first time I have any 6yo.
Based on what I have done this past week, this is what I have today.

BR3-1 COGNISANT, 6g,14d,1600m,tb
MR5-3 HASSLE, 5g, 14d,1800m,d
MR8-8 MONO ROCK, 4g 14d,1400m,c
GC7-7 SWEPTRONIC, 4g, 14d, 1400m, c
GC8-1 TELFIRE, 3g, 14d, 1300m, d

AR5-1 SWISS VAULT, 6m, 14d, 1100m, tc