There is a grudging acceptance that the benefits to the area are worth having but with that comes real reservations that, at its worst and most frantic, the impact of numbers seriously damages and degrades exactly what makes the area attractive in the first place. I suspect that any bolshiness directed at camper vans in particular is to do with their bulk on tiny roads and their self-contained nature having no real need to spend on any local facilities beyond a bit of shopping and fuel. If the 'campers' to which you refer means 'tent campers' then I can see a need to reign them in, but Scottish access rules permit one overnight of Wild Camping as a right ... with the caveat that campers should "respect the countryside", sadly appealing to some folks' Better Natures is a non-starter. Loch Lomond area has slapped on bylaws to control all camping, sadly I can see this practice spreading.
1. Probably not, the Genie is out of the bottle.
2. I think that the single-lane roads with passing places should be written out of the route and, as you suggest, 'Aires' with sewage disposal / water taps / dumpsters created (possibly paid-for, say £5 a night?) created by Highland Council (HC) ... I understand that just such a possibility is being discussed, but I wouldn't hold your breath waiting for HC to spring into action.
3. Accepted that it's a holiday-season 'spike' with this year Covid creating a spike on the spike, that said, even pre-Covid, 26,000 vehicles
over and above normal traffic travelled the route. I can only comment on my own back-yard experience.... the B869 brings over-pressure on the road into very sharp focus, that section needs to be culled from the route, doing so would ease matters significantly while still taking travellers through some outstanding landscape. Two-lane roads cope with NC500 traffic much better and can pretty much handle anything that's thrown at them... sometimes it's thrown very fast! Boy racer convoys giving it some serious welly have been clocked at over 120mph on some of the tempting clear and empty sections. This brings joy to the heart of the Cops who periodically have a field-day with their speed guns, business is brisk. That style of driving is more akin to 'Cannonball Run' and not in keeping with the peace and quiet that typifies the area see
https://tinyurl.com/y447bxpt
Some back-pedalling on publicity would not go amiss, hyped as "Scotland's answer to Route 66" it has become "a challenge" and "The Thing To Do" with its own 'Passport' which can be stamped at various points along the way, this encourages a competitive 'get-stuck-in' driving style rather than an thoughtful and appreciative cruise with pauses to stop and stare.
Here's the view from my balcony, the B869 is on the right. I stop and stare at this quite a bit!
View attachment 86078 click to enlarge.