Hi, as Tabata said, we need to know when you are planning to travel to Lake Garda so that we can give advice with regard to transport options.
The mid-lake area - Garda/Bardolino/Lazise on the eastern shore or Salò on the western shore - would allow you to visit towns all over the lake by boat. The bus service on the eastern side of the lake is more frequent than the west.
As you have noticed, Torri del Benaco does not have a good boat service to other places. It does, however have a car ferry across to Maderno and is also connected by bus to all the other towns on the eastern shore as well as Verona.