I might be able to answer to you.
Riven is off tank but still if you play her too much tanked she deals no damage.

I voted positive, but i think the build is to improve a bit.
Have a look at mine, it's similar on some sides.

you should improve:
- Items: why do you keep having dorans in your build? i mean, long game they are useless..
try adding something tu substitute them in long game.

- Have you ever thought about playing her a bit more tanked? I mean, you probably have seen that you deal enough damage soon after you build Youmuu's, therefore why not build some Magic res or armor?
it would make you more resistant in team fights and more valuable for your team.


this is it anyway..=D

looks very nice. however, here are my questions: since riven is very cdr driven, as you said, i can see the point of yomomu's ghostblade. however, why would you get that, which also gives 20 flat armor pen, right after last whisper? i would not get the lw, since if you get the ghostblade you've already got a good amount of armor pen for an off-tank. i would also add the items you would normally get since you only have 4 core items listed after the triple doran's.