My problem with her is that most of her abilities are tempered in a really lazy way. She has a great passive - but near a wall? What made anyone think you could code that to be anything other than a trainwreck? You could have easily made that passive river-only, or jungle-only, or hell, out of combat for 10 seconds. Instead we got walls which is just stupid.
She takes forever to get on the rock, and drops off almost instantaneously. Her on again, off again passive is more distraction than benefit.
Then there's the "wtf" gating on Threaded Volley. It's already a semi-skill shot in that if you angle it wrong you can whiff the whole thing. Now I have to get artsy just to use the full effect? And whats the trade off? I move more quickly? All of this reminds me of those conversations with people way too into the game that start with "Let's make a really complex character that..."
I'm all for complexity. That doesn't mean it has to be stupid. There was a saying we had back in early WoW that went something like this: Don't leave something broken for the sake of not dumbing it down. The point is, clunky isn't good. It might be complex, but not for a good reason. And that's Taliyah in a nutshell.
I haven't played her since they reworked her W so I won't comment on that.
Unraveled earth is a really cool ability but in both directions, it's wrong. It's good against dash champions - that's awesome. But the damage capabilities aren't great for everything else. It's not good for clearing, it's not good for taking out non dash champions. And I can feel someone coming in here and going "well if you're good enough..."
No. It's about the ROI. Putting in effort with Taliyah isn't' worth it. I can do less with other champs and get more. So why both with her?
Her ultimate, in my mind, is fine. It's weird, and it functions in a way I don't care for, but in the dumpster fire that is this kit, it's the least of the problems, so whatever. it's fine.
You want to fix her, she needs to move closer into a control mage/support role:
P: I want her to roam, but if you're not going to rework this ability to work where it matters in the jungle or river, then turn it into more of a Siege Master ability where she either increases resistance's by 30% near towers, or can do more damage on towers. I don't know, something useful.
Q: If you're going to keep that miserable Worked Earth on there - and it's the dumbest thing I've seen in this game - then allow allies to move more quickly on it, and get rid of that ridiculous mana refund thing. Does anyone go "well I'm running out of mana, better shoot from 'worked earth' for now"
No. You know why? Because no one plays this garbage champion. So there is no worked earth.
W: [see above]
E: I actually don't hate thie ability as much as I made it seem above, but you should give her the ability to recast to pop the ability.
R: She should always ride it. I think that makes it more "should/shouln't I cast this" than giving her the option.