We have been using your premium service for 2 years now, and we've always had problems implementing our own designs on our site, we come from programming backgrounds, so we were excited when we learned about WixCode, but we feel like it misses most of the properties you already have the possibility to config on the editor.
Our main request right now would be to have a way to re-size and move objects through code... Mainly because Wix's editor does not allow for relative sizes, and relative positions, you're just stuck with the 980px area, and right now full pages are awesome, but really troublesome to implement on your editor.
To be able to re-size and move the elements based on page, screen and client size would be awesome... The feature of relative size and position is as old as .css and can probably lead us to not use your service anymore, although the benefits of a visual editor.