Thus no resolutions above or below 1024x768 are planned or possible in Sigma.
With no GUI border we will have more screen estate though, possibly ~100px more on both the horizontal and vertical dimensions.
After all, resolutions above are problematic because of monster AI, and resolutions below wouldn't be used, and since removing the GUI border simplifies GUI code (and thus development time) Whist decided to remove it. This also means bigger inventory / stash / LCS
These are the borders I'm talking about
► Show Spoiler
Of course, I'm not Whist so I may be wrong, but I'm pretty sure about this.