One male and one female grey isn't really a good mix in the same cage as they become mature, if you know what I mean. As the others have said, there's no guarantee that they'll get along as they mature. It's always a crap shoot to see which birds cohabitate well together and which ones want to tear each other apart. Greys can become bossy birds, too.
When my house ran out of real estate with 13 cages scattered throughout the house, I decided to invest in some extra large double stack cages. Got mine from A&E. They don't really need the height of the cage as much as the width. This is the one I purchased and I absolutely love them! https://www.birdcagesnow.com/products/a-e-cage-co-40x30-classico-double-stack-bird-cage They're nice and roomy! This cage will be a perfect fit where your Tali's cage is right now.
I have 3 of them now.