The Dactyl was partly modeled after the Kinesis. It has the key wells and a curved thumb cluster. Still, the thumb cluster isn't perfect and its hard for most people to reach all of the keys.

However, the Dactyl Manuform keeps the amazing key wells and has a completely redesigned thumb cluster.

Its also designed to be easily customizable. There are versions with 2,3,4,5 and 6 keys per thumb cluster. Unlike the original Dactyl, the Ergodox, and the Kinesis, I have no problems at all using all 6 keys per thumb cluster on the Dactyl Manuform. IMO its the best split keyboard unless you want to go for something smaller and use layers to gain access to more keys.

Unfortunately if you can't 3d print the case yourself and hand-wire it, its pretty expensive to acquire one. I just built mine recently and it almost instantly replaced my Ergodox-EZ as my favorite keyboard.