Okay, I can at understand your first choice, even if I disagree with it.

I still don't really think Black Cleaver should be in there, since it puts you behind in comparison to completely Bloodthirster next and Last Whisper is comparatively better as an ArmPen choice. The Brutalizer is also an early-mid choice, not a mid-late choice (especially compared to Last Whisper), so building it after Trinity Force is already too late. Ezreal doesn't really lose out much from not building CDR, since Mystic Shot lowers his CD anyway and that's only on a 4s CD.

Ezreal doesn't really lack in mobility either. Between Trinity Force, boots, Arcane Shift and Flash, 1.5% MS really doesn't do very much, especially since you can get 3% maximum hp instead, which works well for him, since he's a triforce user. In other words, there's 0 reasons to get Fleet of Foot and plenty of reasons to get Juggernaut .

I can understand where you come from Sirell. You are right that usually it's better to rush Phage instead of Sheen when going for Trinity Force. But since Ezreal benefits way more from Sheen thanks to his Mystic Shot this gives a great damage boost which is very nice to have in early. I have tried both ways and ended up chosing Sheen over Phage on Ezreal.

I specifically aim for a high amount of CDR & armor penetration in this build. Since this item provides us way more than that I packed Black Cleaver into it. I guess you might have missed the part stating that.

IMO the points in fleet of food is pretty nice to have. We have more mobility, which is pretty essential for this champ. Putting more points into Offense/Defense wouldn't really pay off that much and I don't think utility is fit for Ezreal.
Plus, the masteries section might not be done yet, but I stated in the summary that there are only MY prefered masteries and that there can be slight changes due to ones own preferences.

Thank you for your point of view!
With best regards,
Heval

First rush is usually Phage, not Sheen. The Brutalizer/ Black Cleaver shouldn't really be there either.

Also, 3 points into Fleet of Foot doesn't really make sense.