No, you're not overthinking it. A short commute like yours doesn't require a specific type of bike, but you'll want to make sure it's comfortable and reliable. A hybrid or commuter bike would be a good choice, as they're designed for both paved and unpaved roads. You could also consider a road bike if you prefer a lighter, faster ride. Ultimately, it comes down to personal preference and what feels most comfortable for you. Just make sure to get a bike that fits you properly and is in good working condition.