@RIot: A Void Champion Playing On The 'Brood-Mother' / 'Hive-Queen' Archetype
As the title suggests, I think a champion based on the 'brood-mother' / 'hive-mind' archetype has significant thematic weight - enough to warrant a champion in the League.
Not something like DotA's Broodmother, as she's a spider and we already have Elise, but an actual 'hive-mind' 'brood-mother' 'insect swarm' 'writhing mass' style champion. I imagine such a champion would offer a pretty unique silhouette while keeping with the purple-pinkish color scheme of the Void. Why the Void? I can think of no better vehicle for conveying the flavor of such a champion. Ideally, and perhaps uniquely, she would be the mother of her children while simultaneously being composed of them. Their collective physical forms and hive-mind would result in something greater than the two - her. (Don't ask me how it works.)
She would be reminiscent of Shub NIggurath, the Xenomorph Queen, the Flood, the Zerg and the Tyranids, the aliens from Slither, and even the hellions from Magic. For an even more obscure, but recent, take on a similar idea, check out Apex from Android: Netrunner!
As far as her personality, I imagine she'd have a multi-layered, echoing voice (a sort of 'we are legion' thing), and, like most Void champions, would be hungry (she has to feed her babies after all, while also conquering new 'hunting grounds' for them), but haughty in a vicious alien sort of way. Lore-wise we could say she is one of 'some number' of Queens of the Void, and whereas Cho and Kog and the others are like the vanguard, she's there to 'colonize' Runeterra. You could even do an event where her arrival signifies a momentous moment in history - that of an existential crisis on the horizon. Think of the moment that Command Shephard in Mass Effect learned that the Reaper they had just killed was just the first. More, countless more, were on the way.
I'm not going to post abilities as they'd probably be scrapped, though I would like to see her be a support (why would the Queen want to be on the front lines fighting doing the heavy lifting? better to sit back and dictate the flow of battle...) and perhaps play with vision or detection in some way. As far as her niche as a support, that would probably be up to her kit and its functionality. She could also seemingly function in the jungle just from a thematic perspective.
I would like to offer some key words that I think better communicate the intended flavor. I want you to think: swarm, hive, larva, drones, parasite, tentacle, seed, egg, hatch, synaptic, slither, collective, brood, implant, insect... I'm sure there's more!
My point is that it's an archetype, a fantasy, that we haven't seen in the League. Not only that but I'd be willing to bet such an idea would resonate with people as well as be identifiable across cultures. I'd love to see what Riot could do with it!