I think if we're going with Wisdom and Valor, the Toa used should be switched up a bit, actually. Going by G1 personalities, the better fit for Wisdom would be Gali, Onua and Pohatu, and Valor would be Lewa, Kopaka and Tahu. Although Lewa would be good for Wisdom after learning things from being possessed twice.
OH! IDEA! The Toa each have to embrace the aspect they become Kaita over before they can actually become it! So like, Lewa and Kopaka completely lack wisdom, at least in the beginning, but over time come to recognize it. Onua, meanwhile, is the type who tends to be content to passively observe rather than take action, and needs to learn to embrace Valor better. You get what I mean? If we go by this, then the biggest boneheads would learn to become Wisdom, and the most passive ones would become Valor.
So the three options would be: Standard Gen 1 Kaita. Appropriate Kaita, Gali/Onua/Pohatu as Wisdom and Tahu/Lewa/Kopaka as Valor. Or the teams needing to grow into their Kaita, making it the reverse of the previous one. What do you think? Maybe this deserves its own poll...
More on topic,
I'm not sure about them simply being combiners with different colored masks. It works with constraction because it has so many different parts, but with minifigs you're seriously limited.