hey hey Amy Mac
as Lin C says, hidden gems are no more "too many tourists". you'll need to find your own, keep it to yourself, with no mention on social media & instagram
make sure you get an IDP (aaa.com/IDP) mandatory in italy for every driver, read laws, rules, signage
several years ago we drove from venice to bardolino for their annual wine festival "festa dell' uva e del vino" late september early october, was fabulous. lake garda has become more popular and crowded with many passing by lake como.
when are you going, how many people and any kids "ages", many small towns/villages you take your pick. i would stay at least 4 days to explore both sides of lake, ferries, water activities, farmers markets, etc "family activities" on lower end of lake there are some camping resorts on the beaches with many activities, mobile home "maxicaravans", shops, restaurants, parking, laundry, grocery store
campingspiaggiadoro.com
laroccacamp.com
campingsanfrancesco.com
click village and will show you what's available for families
earthtrekkers.com/ lake garda: 25 things to do on lake
gardavisit.it (click find inspiration, click lake villages, or click towns on top of page)
summarizes what is there and things to do
lakegardatravel.net
lots of info for you to investigate with your own decisions. have fun & enjoy the beautiful views of lake and mountains
aloha