Here's a light rework for Nautilus, tell me what you think.
[Mockup]
Nautilus Base attack speed increased to 0.650 from 0.613 Attack speed per level increased to 2.2% from 1% Base movement speed increased to 335 from 325.
Passive - Damage is now 2 + 4level + 0.75bonus armor from 2 + 6*level. Applying Staggering Blow on an enemy champion now reduces Dredge Line cooldown by 1 second.
Q - Dredge Line base damage reduced to 60/85/110/135/160 from 60/105/150/195/240. Cooldown reduced to 18/15.5/13/10.5/8 from 18/16/14/12/10. Now has a % movement speed increase that decays over 4 seconds after hitting a champion and the pull is completed of 5/10/15/20/25 %.
W - Titan's Wrath damage reduced to 30/40/50/60/70 from 40/55/70/85/100 now scales with 2.5% of nautilus max health. Is no longer a dot. Hitting a monster now reduces Titan's Wrath cooldown by 1 second, doubled against champions, cooldown increased to 24 from 18. W AOE now starts 25 units behind nautilus.
E - Riptide base damage reduced to 60/90/120/150/180 from 60/100/140/180/220. Riptide cooldown is now reduced by 1 for every champion and large monster hit by the ability, cooldown increase to 11 from 10.
Nautilus should now take a more active role in teamfights beyond that of an initiator and should be actively rewarded for contributing.
His goal should be to do his initiation and get into the fray to apply his passive on as many ennemies as passive to be able to keep CCing the key targets.
He's also greatly encouraged to make use of his auto attacks even when the shield is broken to get it back up and do some damage. His W also got modernized so he doesn't have to position himself in a very specific fashion during his jungle clearing to be able to hit every enemy monster. His W is no longer a dot so he can actually make use of his new attack speed, also most of his damage got moved there.
The % MS on the Q is to allow him to get to actually get into the enemy team when initiating to apply his massive (which is why it's non factor early game).
Anyway say how it should be improved/changed or why it's not a good idea.