As expensive as it is, I've found a Kinesis to be ideal ergonomically, but also to be by no means the end of the story. The design reminds me of a flatter Kinesis keyboard with an angle, due to the split in the middle.

The other part of the story was getting rid of qwerty, and using colemak instead (not Dvorak, which I'm still modestly confused about.) I found that qwerty was modestly uncomfortable to type with due to the dated understanding of how often keys are actually used while typing, which wasn't fixed by the keyboard alone.