Try to totally change where a champ would be played and what items they would build by reworking one of their abilities.
Passive - Star rotation speed scales with attack speed. Stars can crit, and apply on-hit effects.
Turn him into an ADC, lol
Passive now works on enemy champions.
Barrels now have an AP scaling and Lichbane works on them
AHOY MATEYS! YA MISSED ME?!
passive- removed.
Vel'Koz: No change needed, just make sure everybody sees what his crit animation looks like and he's ADC.
Get rid of the limit on Mistwalkers
League needs a Zerg rush champion
Passive- every ability hit, Vel'Koz gains 5 armor and MR.
Vel'Koz top will be a Kraken battle like the Pirates of the Caribbean!
add an effect to his W allowing him to change the type of soldiers he summons between Warriors and Archers. Archers have longer range than Warriors (2X attack range of Warriors) but do less damage (X +30% AP VS X +60% AP) and last longer than Warriors (15 seconds VS 10 seconds). with Archers he does not get bonus atk spd as he would with Warriors. however he gets a +10%/+12%/+14%/+16%/+18%/+20% (based on rank) crit bonus for each Archer out. his abilities also change based on the solider summoned. if he has a mixed army summoned, the Soldiers will do their part of the ability.
Q: with Warriors they will dash to a location (Conquering Sands). with Archers they all shoot at the same time at a location (Firing Sands).
E: with Warriors Azir dashes to them and creates a shield (Shifting Sands). with Archers Azir dashes to an enemy and the Archers shoot at the enemy he dashes to (Covering Sands).
R: with Warriors he creates his wall of 6 shield soldiers (Emperor's Divide) which deals magic damage (150/250/450 based on rank), knocks enemies back and blocks enemy movement for 3 seconds. with Archers he sets up a line of 6 crossbow archers (Emperor's Storm) which shoot out several arrows (5/10/15 shots per Archer based on rank) in a straight line also dealing magic damage and slowing enemies down for 3 seconds. this ability doesn't have combined effects. which ever Soldier is most out at the time that part of the Ultimate will trigger.
with this big ass rework he becomes a support champion rather than a mid laner.
mastery 7 removed
can now "Hook" himself into enemy teams, thus fulfilling his role as the feeding autofill support.
Casting Q on a large monster refunds half the CD and mana, casting Q on an epic monster refunds half the cd and all the mana.
Trying to turn her into a jg. I mean think of the ganks. Q and w out of vision, w and e as soon as enemy sees you and then r for kill.
W now heals her and applies a shield.
Could see it making her a viable top laner.
- Ultimate scales with 100% AP.
- When Q is cast on a monster, it lowers the CD by 50% and always spawns a grave (regardless if it's the Killing blow or otherwise).
- Turrets damage now scales with AD. Turret speed scales with AS. Critical strike increases the rate at which a turret builds up to the laser.
Jokes aside that Sol change sounds really fun.
Now I want Carryelion Sol to be a thing ._.
R: actually turns back time, but since this also rewinds his mental state he keeps repeating all his mistakes creating an endless loop of misery.
Q now deals damage in a circle around him based on number of charges and scales with AP.
R- Final Spark: After a brief channel Lux releases a ray of light that heals every ally champion it touches. If a champion that lux healed gets a kill or an assist she will gain % cdr on it. Soraka who?
now has a 100% AP scaling on Q and Highlander grants an additional 1% attack speed for every 10 AP while active.
R: Now damages all allies, killing entire team thus having wasted enemy 
ulti.
E range now scales with Ap.
1 range per 1 ap
passive : now can be triggered by your attacks vs non champions
i know im a little late but wanted to share this [slayer-jinx-catface]
, e scales with 60% ability power(with 50% reduction for additional) hits. This would turn her into more of an attack speed ap carry.
his windwall extends to protect nearby allies. support yasuo meta
Q damage type changed to physical.
Q damage scaling changed from 50% AP to 110% total AD.
Q base damage reduced by 30.
Is once again a top laner.
Now gains 40% attack speed so long as he has a Meep ready.
Is now run as a hail of blades assassin.
Q mana cost changed from 70/80/90/100/110 to 70.
Is now a usable toplaner.
Her e can now be cast on allies, making her a support.
