Hi Jeremy
Where will you fly into? If Milano Malpensa, then consider swinging by Gattinara (or another of the nearby regions) as it’s not too far out of your way and gives you something different. A day/night in Gattinara might work well, but if you want the same in Ghemme, we can recommend a good agriturismo (especially if you’ll be there at the weekend). Oh, and eat the risotto, which is special around these parts.
Closer to those regions, something like Canelli might appeal if you like Moscato d’Asti, or perhpas tiny Loazzolo for the same plus some fine passito moscato wines (I can recommend a homely agriturismo in Bubbio)
A friend speaks highly of Calamandrana, which has some Langhe wines made there, plus other from the Asti region.
Roero also worth consideration as an alternative style to Barolo and Barbaresco.
Personally I’d choose Ghemme, Gattinara et al, but these are a world away from the Langhe and would only work if an overnight stay at start/end appeals for logistical reasons - perhaps fitting your family wine interest better though? Tim has a very good focus on this region on his website.
Favourite Barolo visit - difficult, as this is such a personal thing. Perhaps Lorenzo Accommasso, but this is the extreme of small, family and with a tasting room more basic than many of us will ever experience. A bare bones experience, but one I still recall fondly. Mauro Molino is in the modernist camp, but we like the wines and the family, with the kids being both friendly and professional. Always a good visit. Burlotto in Verduno also great, for a wonderfully wide range of very good / interesting wines, and Fabio is a gentleman. Schiavenza (with good restaurant as well) and Boasso (very under the radar, but some very good wines including a wonderful Barbera for ~ €10).
Favourite Barbaresco visit. Similarly difficult, though Albino Rocca sticks in the mind in a similar way to Burlotto. La Ca Nova is worth a though. Quite a ramshackled, but spacious collection of buildings at the winery, they were relaxed and hospitable, and the wines are very cheap for what is decent quality.
Many good restaurants, not one I’d go out of my way for, but plenty of good ones including good concentrations of good places in Monforte and little Treiso.
Driving is pretty easy, though there are some reasonably steep slopes & a number of switchback turns. Focusing more on Barbaresco saves you a little in travel time. The only tricky junction is the one on the edge of Alba. Worth pre-planning that on Google maps if you find busy intersections stressful.
Almost everywhere requires appointments, but in return you get almost universal great hospitality.
For local info, including winery contact details, Langheroero.it website is invaluable and this is one of the better tourist offices in Italy - very professional and hard-working.
I’d definitely recommend the large weekly market in Asti, a good day to leave the car parked up, at least in the morning, as there is much to see there (and anyway it takes up a large central square, so getting around by car might be challenging that day!