Very sorry you don’t find it helpful – but the fact remains you are asking exactly that. Nobody has any idea what you are looking for other than a 100% width. maybe – that’s not clear either. I doubt seriously a single person who follows this part of the codex can name off hand more than 1 or 2 themes that offer what you ask for – let alone render an opinion what might satisfy your needs. A little reality check here, okay?
You are not likely to find discussions in this forum about customizing column widths, margins, or the like – this is not the place for that, as the forum name states clearly. If anyplace, the themes and templates forum might be a help – but most people understand that trying to edit all the files needed to change a theme around is a waste of energy and would simply look through all the themes until they find something that fits their requirements out of the box. OR – you could try one of the many CSS forums to see if anyone there could help with adjusting your theme.
Everyone starts someplace. I have only been using WP myself for less than a year, know absolutely no PHP coding (though I have more experience with CSS and markup) – yet I have managed to modify my chosen theme fairly extensively. Nobody can or will do it for you. Scan the themes directory, find one that fits your need, then get to work modifying the colors, graphics, what have you to get what you want like everyone else does.
And BTW … if you think anyone is going to spend their time pondering what “deeper question” you are referring to – you are definitely in the wrong place. The volunteers here will respond to a pointed question – not reflect on what you might me considering from some metaphysical source.