Here is the best "brief" advice I can give regarding selection of brake pads.......
Everyone's braking style is different. And tracks are different. I don't recommend that anyone ever select a pad just because someone else uses it. As for the EBC's, Viper Days Super Stock Champion Tom Glenn has won a BUNCH with Yellow fronts and ONLY Green rears. But then, we also have some really fast guys using and NEEDING Blue fronts and Yellow rears. You're going to find this same situation with other brands as well. If you're not sure, always err to having MORE than you might really need.
As far as keeping the EBC Reds on the back and then just swapping out the fronts, that sounds like a reasonably creative way to handle a street/track situation, and just swap out the fronts. Again, it depends on your driving style. Also, everyone creates their own opinions, but no one should be afraid to run the EBC Reds on the street (that's per EBC). While the Red friction coeffcient is no where near the Greens, it is still virtually identical to a stock Viper pad. In fact, only the EBC Blue range generally requires an early pedal tap on the track to heat them up. Don't even THINK about running THOSE on the street, where cold pad panic stops are always a possibility.
Whatever the brand of pad, or even system, there is no easy shortcut to finding YOUR optimal pad solution. It will simply take some testing and time to learn what seems to work best for YOU.