Zyra's problems in mid aren't going to be fixed by a buff to her Q ratio. Though you compare it to Lissandra's Q, and the ratio is clearly too low. Or you compare it to Vel's Q, and the base damage is clearly too low.
One of Zyra's biggest issues in mid right now is a combination of animation locks, spell delays, and incoherent spell ranges that make it very difficult to actually execute a full burst combo in a timely manner. Here's a list of Zyra's ability ranges:
R - 700
Q - 800
W - 850
E - 1100
Nearly every other immobile mage follows this rule: if you land your CC ability, you can follow up with a full combo. So if you're playing
and you land your hard cc, you can then follow up with the rest of your combo.
The major exception to this rule is
, and she's an exception because she has little or no animation locks in her kit. She can literally cast while moving, so this is a fair exception
But Zyra's spells have the biggest range gap, longest animation times, shortest hard cc duration, and longest travel/delay times. So you end up with a champ in the "Catcher" class that often can't capitalize on landing one of the slowest projectiles in the game. And even if you do land E at max range, you have to move up to cast W, move again to cast Q, move again to cast R, and move again to cast ignite. By that point, the root has worn off, and the enemy just dashes/flashes/walks away/shields or whatever.
There's also the itemization issue since the MYMU. Zyra is completely reliant on stacking early mpen, but she really needs CDR in mid. AD champs get 40% CDR with a full pen build. Zyra gets 0%, and finishing Morello first kills her early/mid power. Now we're facing the rune changes, and nobody from Riot will answer questions about how to deal with the loss of 23+ flat pen from runes and masteries.
They really need to shorten her animation locks and/or standardize EWQ range to within 100 units of each other.