The Nexus 5 charger had a small addition that more or less addressed the problem entirely: it added magnets at the corners of the chargers that would align with something (probably other magnets?) inside the phone, so you would know where the sweet spot was because it would pull your phone and hand into it. But with generic Qi chargers, I would have to fiddle around and check the charge symbol.
I didn't know the official Nexus 5 charger used magnets though. I passed on it because IIRC it was a weird cylinder stand that looked less stable than the generic flat pad I bought. (That and it was a good bit more expensive.)
EDIT: I just played around with mine now, and the margin for error is at least a couple of cm. I think my sense of neatness objects to the offset before the charger does.
In the spirit of nitpicking, all you have said does not bother me at all.
I was responding to a comment that said it was a "total non-issue", and I pointed out various reasons it was an issue for me.
Plugging in a micro USB cable is often quite fiddly, and sometimes the cable can fall behind the table and require crawling around on the floor. Not to mention the cables and ports can be quite fragile and end up breaking or becoming loose. Also if I want to use my phone occasionally while I'm sitting at my desk, I either have to have an awkward cable hanging off it, or plug and unplug it repeatedly.
For these reasons, I found I'd occasionally leave my phone unplugged by mistake and have low charge in the morning. Since I got a wireless charger that never happens.
That said, most of these advantages would come equally well from a docking station, the only problem being there's no standardisation for that.