Hello,
I also use multiple iPads. An iPad Mini2 128/LTE is my personal communicator. I do not have a phone.
My work provided me with an IPad Air2 64. I use it for many apps, including lots of music apps: GarageBand, Notion for iOS, Fm Player, Synth 1 and more.
I have 12.9 iPads available at work, both first and second generation. They are amazing. The newest 12.9 has a great deal of appeal. Tears due to prices tho.
You are not alone in being a multi iPad user.