Calling all Mage Fortune players! I would pose a discussion to you!
I did some sloppy (but not incorrect) math where I took ADC and AP builds for Miss Fortune and I calculated how much damage her ultimate gets from scaling ratios alone. Each wave of her ultimate deals 75% of total AD + 20% AP. Excluding base damage & stats from runes & masteries, while ignoring presumed target resistances, and when rounding to the nearest whole number, I came up with a small list of conclusions:
2768 damage from AP build (Rod of Ages) 2836 damage from AP build (Luden's echo) 3120 damage from AP build (Gunblade) 4675 damage from ADC build (Trinity) 4966 damage from ADC build (Ghostblade)
The items in parenthesis were the single interchangeable ones the 5-item builds. The 5 item builds were created with the idea of giving her ultimate as much punch as is pragmatically possible, in addition to 40% CDR. Yes, I did factor in the potential critical strike damage in the ADC builds. Again, this is flat scaling damage acquired from item stats alone, so all of these numbers would technically be slightly higher with runes & masteries.
Now, you're probably wondering why I'm saying all this. Well, I am a fan of Mage Fortune, aka AP Miss Fortune. When the Marksman overhaul came, I didn't pay much attention to Mage Fortune's performance afterwards (because I'm a fan of just about every champion and don't think to keep track of every single change all at once). Out of curiosity & worry, I eventually came upon her and noticed that her ultimate now scaled from total AD. My first thought was, "Well it CAN'T be stronger than Mage Fortune's ultimate. It wasn't before, why would it be now?"
These calculations I did seem to say otherwise.
It would appear that from items, AP Miss Fortune's ultimate doesn't scale as well as ADC Miss Fortune's ultimate. Given, the ADC builds I used were designed to make her AD ultimate hurt, so they might be unusual to those Miss Fortune's who build with autoattack damage primarily in mind, not her ultimate (for example, the Ghostblade build has only 40% crit chance). Nevertheless, her ultimate seems to legitimately scale better with AD. One of the few things I loved about Mage Fortune before the Marksman rework was that her ultimate was absolutely absurd with AP. But now, it would seem to now be behind ADC Miss Fortune.
My question to you all who love Mage Fortune is, do you feel she is still worth playing over ADC Miss Fortune? Does her ultimate doing less damage late-game than ADC Miss Fortune make her feel underwhelming to you now? Do you feel her AP burst from Q & E make up for her now sub-par ultimate? I am curious to hear your thoughts and opinions, because personally, I'm not so sure how I feel about these conclusions myself.