I like your setup and especially that you want to be able to work without external computer.
Have you thought about Bitbox or anything similar? It's of course not as direct as the DAW-link via ES-9, but works in some ways also without DAW.
After having tried and sold a Blackbox, I suspect the Bitbox isn't for me. I didn't like the experience of using the Blackbox, and I suspect Bitbox might be similar. Reading about it, I got the feeling that's it's a bit menu divy and unpolished. So I went for the Assimil8or instead. Assimil8or has a higher bitrate and so far seems like a better fit for me personally.
Thanks for your thoughts!