[Collection-Thread] Unexplored Concepts
Just a small collection of archetypes, characteristics and themes I made to serve as starting point for new concepts, but since I don't have much time nowadays I don't see why it should just collect dust on my computer.
#Unexplored Themes:
The Painter: Manipulates magic paint to cause a variety of effects
The Witch: A very old lady that mastered curses, poisons or other nasties.
The Faefolk: A champion from the Glade or other place that shows what Fairies can do.
The Parasite: A champion that attaches itself to enemies and allies for debuffs/buffs and other effects.
R shows some traces
The Paladin: A champion that smites evil and supports allies
The Elementalist: A champion that mastered all elements and uses them in battle (Less he feels like Invoker the better)
Should Skins count ? 
The Speedster/Scout: Swift and hard to hit, but lacks burst and needs to utilize a hit and run strategy
The tiny critter with huge impact: Most animals on the Rift are enourmos monstrosities, which is why we need some little fella who can pack some punch (Since Gnar can hulk out he doesn't count)
Token Evil Demacian:
Seeing as Ionia got its black sheep with
, this seems like the time to give Demacia its turn
Not necessarily someone that the Demacians hate, but someone that represents the bad sides of a country goverened by strict laws and traditions.
Literally a tank: Corki was allowed to bring his bomber, so don't tell me his colleagues from the artillery corp have a good reason to miss battle. Could work as a tanky ADC or as a ranged Juggernaut.
#Unexplored Playstyles:
The Construct: A champion that is at it strongest at full health, but gets weaker when he gets damaged
The Visioner: A champion that specializes in providing vision
The Wrestler: Juggernaut with high CC instead of Damage
The Commander: This champion just has himself and the ability to manipulate minions to achieve victory.
The Saboteur: A champion that can sneak up on towers and take them down when nobody is looking. Not necessarily an assassin, but a stealthy and mobile splitpusher.
The Thief: Looting bodies doesn't count for this. The less he openly fights the better.
#Unexplored Weaponry:
Ball and Chain (Seems like a Juggernaut thing) Slingshot (young kid or yordle ADC) Fans Grenade Launcher (main weapon which the whole kit focuses on) Harpoon Wires (Think Walter from Alucard) Chainsaw Umbrella
#Undeveloped Potential (Themes that already exist, but are open for further exploration)
Regions of Runeterra: Vodoo Lands, the great barrier etc. seem to have been swept in the back of Riots mind
The Darkins:
Aatrox isn't the only one which means there could be others (Better, if they feel different from Aatrox)
? ?
Techies: Rogue Securitrons, emotionally unstable Terminator or hyperintelligent toaster, if there is one thing you can never have enough of, it's robots... and ice cream
Insects: Apart from Spider and Skorpion this theme has much more to offer (I personally don't think Voidborn count since they are aliens)
#Not bad Riot:
The Blacksmith:
Where's the blacksmith?
There he is.
Scythe (melee)

The Terraformer:
A champion that is all about enviromental advantage, creating Walls and other obstacles.
seems to somewhat fit the bill (W obstacles and R wall).
Amphibious Champions:
Gromp might need some assistance

Druid/Shaman: Someone that manipulates ancient powers and spirits and is in tune with nature (Unless you have a good idea exclude Aura totems, since they lack visual impact and gameplay)

The Hextech Soldier: Utilizes Gadgets and advanced Weaponry to get an advantage on the battlefield

The mounted Hunter: Uses his trusty beast to chase or circle enemies, while picking off targets with his weaponry.

is a mounted hunter, sort of.