> Solars' role was to be beacon of hope, rulers and leaders of men, had aura of nobility to rally people around them. Heroes of humanity. And Lunars were their opposites.
Nah. Some of the Solars had that, sure - the Zeniths - but others were puissant warriors, brilliant technologists, and negotiators and diplomats par excellence.
The Solar's role is to be human ability turned up to 11. They are the best at what they do - but what they do is limited to the arenas of human capability. They are the ultimate fighters, kings, priests, explorers, hunters, diplomats, courtesans, tinkerers, sorcerers, thieves and assassins. The way other splats compete with that is to have niches that go outside of human ability - elemental effects, shapeshifting, fate dickery, etc.
One of the problems with Lunars is that their role has either been poorly defined. They were supposed to be the Solar's mates: their complement, not their opposite (the opposite of Solars would be Abyssals).
In my head anyway, the complement is defined on an individual basis, rather than as between the splats as a whole. The Solar Fightin' Man would be mated with a Lunar socialite, to fill the gaps in his capabilities. The Solar God-King, all righteousness and purity, would have a Lunar who was willing to get their hands dirty. A Solar Sorcerer would have a Lunar bodyguard, to handle the physical threats that were outside his ambit.
That was their role in the First Age, anyway. Then the Solars went mad, abused their mates (and everyone else), and got locked away for millenia. In their absence, the Lunar's have had to determine their own purpose for being. That's ok though, as part of a Lunar's nature is adaptability. They used to adapt to the nature of their Solar mate, now they adapt to whichever task they set themselves too (in 1E that task was "smash stuff", in 2E it was "protect Creation", and in 3E it's yet to be really nailed down, but looks to be "break the realm")