I gave your mod a try and was frustrated with the lack of settings to change the look and feel. I use the mod Gui Unifier to remove and simplify some gui elements. It would be awesome if you could either add settings to control the fame and background. Or add compatibility/integration capability with Gui Unifier so your mod could match the rest of a custom gui.

Thanks.

Thanks for the feedback, the mod is a work in progress but I can take a look at your suggestion and see how we can use similar fundamentals to improve the layout, display and functionality.

I'm desperately hoping for a button on the topleft gui as OP stated, or at the very least a hotkey to toggle on/off the main window. At the moment I'm having to resort to disabling every feature every time I want to minimize the window, so as not to take up unnecessary space when I'm not looking at it.

I'm thankful you're making this mod @AceDubs.
I have a related suggestion: Remembering the position we put the HUD to with the save would be awesome. So it doesn't conflict with other GUI elements one might have. I recently installed Sort Me (https://mods.factorio.com/mod/sbSortedLogistics) and it does this.