For Dragonlance I'd do a forking Paladin subclass called Oaths of the Measure. 3rd level is the Oath of Loyalty (Knight of the Crown). 7th level you can continue in Loyalty or initiate into the Oath of Courage (Knight of the Sword). At 15th Level, if you had previously initiated into Courage, you can opt to initiate into the Oath of Justice (Knight of the Rose).
For Wizards of High Sorcery, I'd do three dual specialty wizard subclasses. The School of White Magic would focus on abjuration and divination, the School of Red Magic would focus on illusion and transmutation, and the school of Black Magic would focus on enchantment and necromancy. There would be a sidebar on the effects of Krynn's moons on these types of magic, but that wouldn't be hardwired into the classes.