On a standard keyboard, I use fingering something along the lines of:
Show Image
(http://i.imgur.com/oTgR4Kq.png)
If you’re going to the trouble of making an entirely new layout, I highly recommend shifting your right hand to the right by one key, to move some of the burden from your right pinky to your index finger(s). Making right shift, return, and delete easier to reach is a big improvement.
(Or if you can afford it, just get a better physical keyboard layout, and worry about the logical layout only after you have a physical layout that you like.)
I really like this, the totally different layout sounds like a steep learning curve that should be intertwined with having the job done, which is too risky. At the end it would not worth the effort, reaching pretty much the same efficiency level.
Solemak (http://kennetchaz.github.io/symmetric-typing/solemak.html)
Show Image
(http://kennetchaz.github.io/symmetric-typing/graphics/keyboard_solemak.png)
I've heard of a lot of people complaining about the S in Colemak, it seems to be hard to learn because while still on the homerow, it moves one place to the right. So I can imagine this layout being of potential interest to Colemak strugglers. Doubtful on the other two though.
I wouldn't fancy typing OK frequently on it though. Pinky overkill? Maybe move the K to the bottom (where the qwerty-B would normally be) and use the right-hand index finger for it?