Its hard to say what "good smelling" means here. Some amyl solvents can have a fruity or sweet smell. Certain esters that are used for solvents can give a bit of a sweet odor. These can be very slow in evaporating, so you might smell them for quite a while. Eventually they should go away, though. The same holds true for some of the nasty smelling compounds.
By itself NC has very little odor. It's all from the additives.
I was reading some things about Gibson's lacquer spraying and it appears that they are using a robot to spray the finish (don't know if custom shop does), and the it's electrostatically charged to draw the resin to surface, much like they do with car finishes. (Josh might be somewhat familiar with this process). I have no clue what additives they use to make the lacquer react properly.
I think HinesArchTop has the right idea. Some vanilla extract should do the trick! Just don't get too much, as it might attract the bees when you're playing outside.
As for the checking, it's going to be hard to determine if they are using pure NC or adding something like an alkyd or phthalate to make the film more flexible. And looking at a safety data sheet may not tell you all the ingredients, since it only has to report the hazardous materials. The Behlen based lacquers appear to be primarily NC, but if you look closely, there is a bit of silicone in there that probably makes it feel a touch slick. Sometimes you see a small percentage of silica which is used to give a lower gloss, like a satin look. Cardinal lacquer is definitely plasticized. Sherwin Williams is resin modified. I can't find info on Akzo Nobel. A lot of people that sell lacquers are just repacking from manufacturers.
Ok, I've nerded out log enough.