I agree that it sucks that Ahri no longer has access to grievous wounds due to her not wanting flat pen (since she has true damage), and simultaneously doesn't want Liandry's still (doesn't need the health, and I believe the damage ramp doesn't affect true damage either). She went from having 1 strong item (Liandry's) being inefficient on her to two.
That said, new Ludens is a buff to her relative to old Morello - the extra damage ratio an item earlier helps her mid game. Spellbinder is likely also a buff on her at 2 items, however it requires you to use the active well (which isn't a given, especially at low Elo). Deathcap buff with void staff nerf is great for her (she didn't benefit as much from void staff as other champions due to her true damage so nerfing it helps her, while due to her lack of synergy with other item options she was one of the few mages to consistently build deathcap before, so the extra 5%ap and better build path are a straight buff). Rylai's getting an ap buff is nice for her too, if she decides to go that way.
The problems I find Ahri has now:
Without the old mana restore passive of Morello, I can't stick around after won fights anymore. I lost a game due to this yesterday. Win a fight with staggered kills and can't keep pressing on as the first enemies respawn because I don't have the mana to help kill them and what could have been a game-ending push wasn't (which meant we eventually lost). Ahri has always had mana problems and without mana restore on take downs, she simply becomes useless after a big team fight is over unless she has blue or recalls.
Liandry's may be overturned, which sucks since she doesn't use it well.
Ahri can't opt into grievous wounds without seriously hampering her damage, which makes her a lot easier against healing teams than before. Especially now that Morello offers this on all hits, ADCs will opt into executioners even less, which makes healing comps a lot harder for her. At least she can take ignite though.