Yeah, Kii is pretty nice. Great suggestion--I'm glad I bumped. So far Kii seems pretty comparable to Thumb, but I especially like Kii's more convenient way of accessing the arrow layout, which provides the full suite of copy/paste stuff that Thumb doesn't have. The only drawback is that Kii doesn't have Thumb's kind of one-handed (squeezed to one side) layout. I'm able to compensate decently well by customizing key size and spacing, but the 'p' and backspace keys are still uncomfortable for my left thumb. Kii does have some "squeezed" split layouts, but they stick a numpad in the middle of those. I would think they could easily make a squeezed standard keyboard, so I emailed the dev a request.
Galaxy S 4 I9500 (CM 11.0 ROM (Android 4.4.2), PhilZ Touch CWM 184.108.40.206)
Galaxy Note 2 N7100 (CM 11.0 ROM (Android 4.3.1), PhilZ CWM Touch 220.127.116.11)
past: Galaxy 7.7, Galaxy Note 1, Galaxy S 3, Galaxy S 2, iPhone 3GS, Motorola Milestone