I agree about some modellers going 'over the top' with panel lines etc, as we've discussed recently. Strange how it mostly seems to be those that are the 'rivet counters', who will argue the toss about the colour shade being point twofive stages the wrong side of a Pantone scale, or FS colour spec, for example!
Personally, I try to keep any panel lines and shading on my models as 'scale' as possible, and sometimes don't even add any 'enhancement', depending on aircraft type, scale etc.
I normally try to work to a viewing distance of around 12 inches, or the equivalent for a full-frame picture of the model, depending on size/scale. At this distance in 1/48th scale, the distance in 'real life' would be, of course, 48 feet. If the panel lines show up drastically, other than those on certain aircraft that would be prominent on the actual aircraft, then I know I've overdone it. If done correctly, the lines should virtually disappear, apart from those mentioned above, and should become more visible the closer one gets to the model, particularly in photographs, as per the full-sized original.
A (minor) problem with kits of some aircraft, is the way surface detail is presented. Normally, it's engraved (recessed) these days, and many shun the 'old fashioned' raised detail. However, quite often, a combination of these would be more appropriate, in order to give a more realistic likeness for a particular type, where panels might be butt-jointed, overlap and so on, unlike the relatively even, smooth surface of a model. This, of course, becomes more apparent the larger the scale, and I remember many years ago having a bit of a 'to do' with some 'know it all' about the way I had replicated some overlapping panels, by scratch-building, on a 1/32nd scale Spitfire. In his 'considerd opinion', it looked totally wrong, and couldn't possibly represent the real thing. After telling this particularly obnoxious individual that I had severe doubts as to the validity of his parentage, and suggesting that he remove himself in a particular fashion, I also suggested that he take the first opportunity to look closely at a real Spitfire! (I'd been informed that he had never even seen one close-up, whereas, at the time, I had just spent two airshow seasons working with four Spits!).