The Enhancement with higher defense is supposed to be Steadfast. I have received Steadfast enhancements as quest rewards and it is +end, + shield, +Def being weighted to the defense value, but if I craft a Steadfast enhancement it is weighted towards shield, and yes I have the purple recipe for steadfast. Really hope they fix this soon so I can craft enhancements for my armor. I don't want to do it yet in case they don't make the fix retro for installed enhancements.