What kind of apps are you writing in Moai? Games or something else?
I ask because there's a huge problem with rolling your own UI that you might not be aware of: accessibility for people with disabbilities, especially blind people. All of the major desktop and mobile platforms have accessibility APIs, which their native GUI toolkits (or dominant ones, in the case of desktop GNU/Linux) implement. These APIs are very tricky to get right in custom implementations; I've seen many projects get them wrong, especially on Windows, where I have the most experience with this stuff. If your app isn't something like a game that really can't be accessible to blind people unless it's specifically designed for them, then it pays to use the native UI toolkits.
I work in the Industrial sector - we do not have the requirement of supporting hindered folks. Rather, the GUI has to be operational in extreme conditions ..
I ask because there's a huge problem with rolling your own UI that you might not be aware of: accessibility for people with disabbilities, especially blind people. All of the major desktop and mobile platforms have accessibility APIs, which their native GUI toolkits (or dominant ones, in the case of desktop GNU/Linux) implement. These APIs are very tricky to get right in custom implementations; I've seen many projects get them wrong, especially on Windows, where I have the most experience with this stuff. If your app isn't something like a game that really can't be accessible to blind people unless it's specifically designed for them, then it pays to use the native UI toolkits.