Hi, in case you haven't found an answer to your question already, I'm not hugely familiar with Balloch but pass through regularly.
If you just drive through from the A82 towards Balmaha and Stirling it doesn't look very "walkable", but Balloch sort of merges into Alexandria and it does have a Main Street area with banks, train station etc, and residential areas nearby. In fact I'd say Alexandria station is within walking distance of Balloch station.