I missed the kick starter for the Keyboardio Atreus.
I’m looking forward to the launch so I can order one retail.
In short it’s a split layout ortholinear similar to the Planck.
Two killer features for me are Bluetooth (and wired) and QMK firmware that allows layers.
I looked for a while for a nice split mechanical keyboard and I found all sort of crazy things, including the ones from [1]. In the end, I decided to try the kinesis gaming kb [2] and I really like it! (so much so I even got one for my brother :-) It has some cool macro recording keys and extra buttons to map and other features. Caveat: it is wired.
1: http://reddit.com/r/mechanicalkeyboards 2: https://gaming.kinesis-ergo.com/
The key is to pull it off your desk and put it in your lap. You end up typing with your hands on your thighs, which feels quite natural and relaxed.