AP Tristana

Would something like this make AP Tristana more usable?

Rapid Fire AS: 30 / 50 / 70 / 90 / 110 (+1% per 10 AP)

At 500 AP, that would be an extra 50% AS, for a total of 160% bonus AS at max rank. At level 18 with no other AS modifiers, that would give Tristana ~1.87 AS during Rapid Fire.

At 800 AP, that becomes ~2.07 AS at level 18.

I was thinking about this because Tristana's AP ratios are still strong, but she needs to stack Explosive Charge for said strong ratios. Stacking Explosive Charge requires Attack Speed, which Tristana won't get much of by building AP.

I'm not sure what a "balanced" ratio for the AS per AP would be, though. I just kinda guesstimated.