After consulting my vet and finding Aphrodite in good health, I've moved her into the living room with Zeus. Zeus, my 'tiel, is positively fascinated by her, and this seems to be reciprocated. For most of the morning Zeus was sitting on top of Afro's cage singing to her, and she was sitting on her swing and twittering back. I had some free time in the afternoon, so I settled myself within arm's reach and opened the little girl's cage. It took an hour or so, but she eventually wandered out after Zeus popped his head in and ate some of her food. They spent most of the evening on Zeus' manzanita stand, and took a nap together side by side after chowing down on some spray millet.
I'm really glad that they're getting on so well. Zeus already seems to be less interested in obsessing over objects (he's been picking a new one every other day and guards it rather aggressively. Lately it's been my laptop, which can be a real pain in my fingers!), and was instead fawning over Afro. My gamble is paying off so far, but it's very early in the relationship and I'll remain vigilant.