Upgrading your coffee maker is a fantastic idea. I recommend checking out the Lennox manual. While it's not directly related to coffee makers, the manual approach can be quite universal. Now, for coffee makers, consider factors like the type - drip, espresso, or single-serve, the brewing capacity, and additional features like programmability or a built-in grinder. Online reviews and user experiences can also provide valuable insights. It's all about aligning the coffee maker with your preferences, whether you're a casual coffee drinker or a coffee aficionado. Happy brewing!