FrogPad might have a solution for you. They have am alternative that you’ve just got to see to believe. FrogPad is touting one-handed use and full-sized keys, albeit fewer of them.
These units are not yet available for commercial sale, FrogPad is looking to OEM them for licensees. They did say that there is a single licensee though, who is hoping to help FrogPad prove the concept and spur the initial sales needed for a full production run.
If you can’t wait for production units, you can buy one of the samples that become available early next year for $230.