Jaeger, The Shadow Stalker [CHAMPION CONCEPT]

So, i've been building this champion's kit and build literally only a week ago and it hit me, why not make it a thread.

Stats: Health: 540-1894 Attack Damage: 55-97 Mana: 350-998 Attack Speed: .625 (+0% - 53.4%) Armor: 26-74 Magic resist: 34 Move speed: 330

Passive: Cripple - For every auto attack Jaeger lands on a enemy champion, it add's a stack of Weakness on the target. Each Weakness stack decreases the target's movespeed by 5, the stack will disappear in 5 seconds if not attacked by Jaeger within that given time. Duration of the slow will be 3.5 seconds after the third shot. Max stacks a target can receive is 3. Cooldown will be 15 seconds after the third auto attack.

Q: Leg Shot - Jaeger fires a special bullet at the target. If the target has 3 stacks of Weakness on them, they will be rooted for 1.2 seconds. (The skill will be a skill shot required, and will hit minions if in the way. Range will be 1250.) Cooldown will be 16 at all levels. Cost: 45/50/55/60/65 MANA

W: Surprise - After 2 seconds, Jaeger becomes invisible for 5/6/7/8/9 seconds. While stealthed, he gains 15% movement speed and loads a special bullet in his barrel. His first auto attack out of stealth will apply the 3 stacks of Weakness upon the target. The bullet has a 33% chance to penetrate the spine of the target and stunning them for .7 seconds. Cooldown will be 24/23/22/21/20 per level. Cost: 70/75/80/85/90 MANA

E: Ghost Stance - Right after landing a guaranteed critical shot onto the target dealing 3/5/7/9/11% of his target's missing health as bonus physical damage, Jaeger goes into Ghost Stance and hides himself for 3 seconds at all ranks. Movement speed will be increased by 10 during the stance. (Range will be 850). Cooldown will be 19/18/17/16/15 per level. Cost: 65/70/75/80/0 MANA.

R: Predator - Jaeger goes into a state of complete tranquility, stealthing for 7/8/9 seconds while enabling him to attack enemies while hiding. While in Predator, his range will be increased by 100. However, Jaeger will be completely rooted and not able to move from his selected location. If he happens to be hit while in Predator, he will show and the cooldown of Predator will go into cooldown. Cooldown will be 125/110/105. Cost 110 MANA

Not sure if his kit is too op, he's a adc if you didn't notice lol. Let me know below and tell me what I need to fix. thanks !