trinity force with those cooldowns and ratios seems a bit suboptimal, but i wont vote...

a hextech.revolver earlier help u very well :)
i test it, and it´s pretty nice with "w" or if u want to fly and use "e" u gain a little extra hp to escape safetly.

the only thing i would change is athmas -> sunfire cape it deals more dmg with "w" and passive dmg all the time + more armor ;)

Seems like a solid build. Since you are going 21/0/9 would spell vamp quint's help the early game sustain? I find that I'm chugging pots all day and still not having enough Hp to safely tank before level 4 or so. Also what about sunfire cape? It goes well with W and seems really good when chasing or late game when they dogpile you.