The way I'm envisioning it, time is mutable on the plane of Death. Its not useful for any exploitative purposes and it isn't time travel, its just that a minute can seem like a lifetime or 50 years could pass in an eyeblink. Have fun with it, use it in your roleplay if you like. Don't abuse it.
Caesar, if you don't like it let me know and I'll edit.
The plane of Death is, in effect, your realm, like Kinaré's Cave is hers. So the workings of time and even laws of nature in their realms are determined by the Gods themselves. As long as people will not stress the boundaries too much, we'll be alright.
I also find it curious to see the Lady testing the extent of her invisible opponent's power.
Somehow I can't see the Lady ever creating a realm of her own in that way, but I might do something with temples later. She's a less Elemental god than Death, Destruction, Growth, the Sea or even to an extent Dreams. A plane of Strife doesn't really make much sense.
The Lady is an embodiment of strife. That doesn't always mean fighting, but she's got a pretty keen grasp of human nature. As much as this is testing her invisible opponent's power, she's testing (Kinare's) level of control. I'm planning a few moves ahead any way.
I wouldn't say I was disappointed in my expectations. Pleasantly surprised is about right. I also like the contrast in attitudes that's developing between the chosen servants of the different gods; where Elti more or less hated the Lady by the end (in part due to her failure and the futility of her quest), Isra died hand in hand with Mahet. Nevertheless, both remained loyal.
Edit: I'm also not 100% why I had Elti's reunion with the Lady be such a sour one. It just seemed the appropriate response to an ultimately fruitless lifetime of servitude, especially to such a callous (if not actually uncaring) master.