Lesa is a pretty lakeside town, but there’s not a lot to do for a day trip.
Do you you mean Stresa? Much more to see and do there for a day trip and there’s plenty of direct trains. There’s the town itself, the long lakefront walk, easy access to the islands and the cable car to Mottarone, including a stop at some beautiful gardens at Alpino.
Arona is a bigger town, though its nice too and has some attractions, like the giant San Carlone statue, it’s busier and less touristy than Stresa. It will also take longer to get to the islands.
All things considered, would prefer Stresa for a day trip.