Love the RK006... use one as a permanent fixture in my studio and just ordered a second for performance setups.
Would love to see you add more filtering options to it with future firmware upgrades. Most especially note range/filtering.
A common performance setup of mine involves doing splits & layers of multiple MPE hardware synths while playing them with a single Seaboard Rise 2. I am currently achieving my midi processing like this by routing the midi through a rack of MIDI devices in Ableton Live. But would love to be able to achieve this sans laptop.