Hi Brian
I’m afraid I’ve not been to or even through Nizza Monferratto yet, but can offer a few ideas not too far away.
Agriturismo La Corte at Calamandrana is a regular destination for a forumite on wine pages and he speaks very highly of it. Is this the place you are staying? If not, it must be in walking distance so worth seeing if they are doing evening meals (or sunday lunches). Agriturismo meals can be wonderful, even if careful pacing is needed as the dishes mount up.
We stayed not far to the south in Bubbio, at Tre Colline in Langa. Not much of note to Bubbio itself but it was nice to stay there. The agriturismo did a slightly rustic traditional banquet, but there were occasional dishes where Paola betrayed some very fine appreciation of flavours. A meal here is a very convivial meal out, one where we always went with the house wines as it felt more appropriate. The following week we were indulging our wine geekery in Barolo. Max (Massimilione) is a lovely warm and friendly host.
The walking around Bubbio is very good, on deserted single track but tarmacked roads. However I suspect similar walking can be found that can start / finish where you are staying. A few years ago we connected up with an organised walk from Castino that took in a truffle walk (we’re convinced the truffles were pre-planted by the truffle hunter, but we had a good chuckle when he dog spotted the guy was talking and wolfed down one of the truffles. Big doggie grin!). The other walk took in the scenery and it too was lovely.
Acqui Terme is worth a visit, especially on the market day WEEKLY MARKET – Every Tuesday and Friday morning until 1 p.m. throughout the historic centre, Corso Italia, via Garibaldi, piazza Orto San Pietro, piazza Addolorata, piazza San Francesco, via M. Ferraris and Piazza Ferraris
We parked a short (5 mins) walk from the centre here Google Maps which had the advantage of taking us past a very good bread shop on the way into the city - some wonderful wholemeal / seeded / granary rolls which aren’t too common in Italy.
The centre of Acqui is very easy to cover on foot, even for 75 year olds needing to take it a bit easy.
Additionally/alternatively you can book in for some thermal spa treatments, but booking in advance seemed to be the way to go. The owners of the accommodation may be able to help here / have discount cards.
Loazzolo is a similar distance from you, and a nice option to indulge wine geekiness on the local dessert wines. This is a tiny DOC - smallest in Italy apparently. The road through it is incredibly winding for such a small area. The wines major on Moscato, but in a passito style as well as frizzante, and they really are very good. Other grapes too here including Brachetto. If your parents aren’t hugely into wine, then maybe some wonderful sweet wines might appeal.
I’ve not been to Canelli, but this seems a sensible day trip to include, maybe taking in the historical cellars housing the sparkling wines.
Finally, I recall a forumite staying very near - IIRC in winter, so it might even be very recent. Definitely worth a search of other threads to find out who & PM them questions.
Hope this helps
regards
Ian