I love the thought of being able to multi-track audio right to my iPad, and I like your idea of using the iPad as a middle man to get those tracks back out to a mixer, but… why not just eliminate the middleman?
What I’d really love is an Overbridge USB “hub” that you plugin to your Elektron device, and all it did was provide multiple outs - at least enough to separate out common elements like Kick, Hats, and a couple of Melodic parts.
I don’t need a full blown Overbridge Mixer (Tonverk?) device, though that would be awesome. Just make it really easy to get at least a couple more discreet outs on OB capable devices without requiring anything but a USB dongle.