Diana changes don't solve her problem
While the Q CD buff is a good change, the rest is a bad direction. It buffs Diana's great late game, especially her splitpush, which is btw one of the best in the game, but takes away from her atrocious early game, when she struggles the most. While I prefer playing her midlane (mastery 7), it's also a huge nerf to her early jungle clear.
If anything, keep her passive attack speed and add the E buff -20% at each rank.
Or the best, don't buff her splitpush potential, which she doesn't need to, but buff her mana costs instead. As someone who doesn't like to build RoA I find myself without mana too often, two ability rotations are enough.
W: Pale Cascade: 60/70/80/90/100 --> 50/60/70/80/90 perhaps?
And E: Moonfall also costs imho too much mana for what it provides: 70 --> 50
