I picked up the (back, del) (enter space) thumbs layout from Kinesis, that feature alone has saved me years of strain, id wager. The shape took a bit of time to get used to but I was back at my average wpm speeds in a couple of weeks. Not as much of a learning curve as Ergodox with its layers but the curve and ortholinear layout take a bit of adapting to, though that's true of the Ergodox too.

I kind of wish split keyboards were standard, instead of the default mode being all squeezed into the same 38cm wide form factor. The MS Natural keyboard was a step in that direction, split keyboard with a JUMBO space bar, but I wouldn't nominate it for the new standard..

While the kinesis doesn't have layers like Ergodox, it does have macros and you can remap keys via the hardware of the keyboard itself. I've been using an Ergodox for a few years now and got used to the layers but found the switches needed replacing a lot sooner (maybe I should have gone with a different set) and found the firmware update process for remapping to be annoying and tedious (even though they've gotten it down to about as few steps as is practical). Ergodox is more powerful in the abstract, though.