Not a critique, but possible embellishments ... (respectfully)
heads for pennies, tails for dimes,
orientation of coins changing from upside right to upside down ... in opposing directions coppper vs. silver

I suppose you could also contrast the government heavy (dime) FDR "New Deal" platform with the more liberal "Emancipation" and freedom policies from (penny) Lincoln's presidency. But that might be going a bit too far