A List of Random Concepts..How have they not used some of these yet?

Where..is...our... weather dragon...

A Queen Bee concept, an assassin with utility. Melissa, the Hive Queen! She could summon swarms of bees to attack people, plant little hive things around the map as wards/traps, splatter slowing honey on the ground, etc.

A duo concept of any kind. If anyone knows of Chaos Online for example.. may I direct you to the Agni Brothers? Maybe two Yordles pushing around some sort of mobile catapult/cannon, etc. Fire the cannons/rocks!

Some ethereal thing like Io from Dota 2. Does League of Legends need its own whisp?

A Djinn concept. He/she has a flying carpet, can avoid unit collision.. and builds up 'Static' as he/she moves. At full static, their spells can have other effects. The ultimate could be '3 Wishes', which well.. could be something activated up to 3 times before going on cooldown.

Some spirit-like character that can go into the bodies of others (a character with an ultimate similar to HoN's Empath).

Some demonic-creature warlord character with a hugearse weapon and hellfire.

Another TRUE Mage of some sort. It could be an Umbramancer.. Geomancer.. whatever.

A satyr/stag-bum guy that plays his panpipes. I've once pretended to make a concept of this sort of thing. He had a Q skillshot that CHARMED (a lovely melody on those pipes), a W that planted these patches of vines that could be stuck on walls and the ground..and snared/revealed enemies that came near them if they tried to then snap the vines attached to them, an E that targeted a single enemy, slowed them slightly and caused all ally minions and neutral monsters to aggro onto them for a time..and then the ultimate, which was an Area of Effect Fear sort of thing (a demoralizing song). His passive was some sort of thing called Fanfare where he'd grant movement speed bonuses and mana regen bonuses to himself and surrounding allies when he used spells. He was intended to be played as either a jungler or a support.

I had a psychic guy once. He was bald, blue skinned.. had a mage/support-ish theme surrounding true damage (albeit not overpowered - psionic attacks straight to da mind) and superior map vision through clairvoyance, etc.