I've been looking at the open PRs recently, and particularly a suggestion on the one relating to ender air bottling caught my eye, talking about a dedicated item for capturing ender air. The discussion continues with:
I'd be fine with the idea of using the Botania brew vials/flasks for this. A new dedicated item seems a bit much.
Botania has its own, more magical fluid container items already, the managlass vial and alfglass flask. So this suggestion (which primarily gets rid of all the awkward mod interaction conflicts) proposes using those instead of mundane glass bottles to capture ender air. The open question is how to handle the different container sizes of those two items.
My suggestion: A managlass vial of ender air contains one unit and is throwable, while an alfglass flask contains two units and is not throwable. When using either for crafting you get the container item back with one fewer units. This would introduce only one additional item to deal with in autocrafting situations, a half-full alfglass flask of ender air. Crafting recipes could use the three ender air items (vial, full flask, half flask) interchangeably.
Alternatively, the flask is single-use for crafting as well, but has other potential applications (e.g. throwing it results in a larger ender air cloud, more ghast tears, etc.) or could be used in more efficient crafting recipes.