Gangplank Itemization build

I'm trying to work up some proper items in mind for gangplank based on the new items brought out.

five out of six i've decided to stay stationary on are

being for his Q and E procs along with the cooldown reduction for faster casting.

for sticking to enemies and escaping if need be. this also makes him quite beefy with good armor and health. I also take scaling armor runes up to 34 bonus armor by level 18 (+1.82 armor per level)

for his W and for with how much damage his E's deal to enemies in an area radius. This also goes for his Q procs and auto attacks. I also take the same scaling runes for magic resistance so I get 34 bonus MR by level 18 (+1.82 magic resistance per level)

is obviously to cap his CDR at 40% and to grant him more sticking power with his E and with and

What I have yet to decide upon are these three last items.

, , and

Is obviously for wave clear and team fights.

is for tower pushing and I can only imagine quick hit and run tactics

and is for sticking power and dueling power.

But I bet you all can get the gist of my mentality with this build. Gangplanks' E provides 50% armor ignoring/penetration to begin with so saying he needs penetration is ... really redundant.

Either way... I need some feedback with the logic behind all this so far.