Gangplank too broken?

Is Gangplank too OP? The short answer is undeniably no. His early game is trash, his mid game is only viable if he somehow gets fed early game, and his late game happens later than every other champion and is so-so. He is not a viable tank, bruiser, mage, or adc. On the occasion he does lane against a matchup where he wins, the real question becomes "wouldn't it have been more efficient to play literally any other character in that role?"

Truthfully, he feels like he doesn't fit well into any role except bruiser, but he gets bullied by all other bruisers. And tanks. And mages. But let's focus on him as a bruiser. He's very squishy compared to most other bruisers while also lacking hard cc or tremendous burst damage. His sustain is also very very weak: while his w does remove any cc on him, it's on a very long cool down and the heal is unbearably weak for the mana cost. His ult isn't terrible for assisting across the map with a slow, but the damage is painfully low and scales off of AP.

My thoughts on fixing gangplank -- Ult should scale off AD or maybe armor or health or anything but AP. Or lower the cost of the first upgrade on his ult (or both?). W should scale off of health. Allow Q to apply his passive for half passive damage. Remove the degrading health aspect of the barrels and just give them 1 health.

I don't want to see Gangplank to become the next stupid OP champion (again), but would like him to be more viable as a champion than he currently is (which is worse than before they buffed him before the rework). I think this needs to be through either increasing his survivability or increasing his early ability to do burst damage.

What are your thoughts?