This is kinda silly, but drinks is just another branch of food. And I'm not for one on the alchohol train with brewing beer and fermenting wine. However, making teas (for morning and rain), shakes (be it ice cream for taste or protein for strength), juices, coffee beans (with included coffee bean crops? cause who doesn't like a nice java once in a while?) and etc.
I love the idea of tea and wine, maybe we could grow our own tea leaves and grapes to create out own.
Although, continuing off this, I think having alcohol would be a good idea. Maybe not beer, but wine would be awesome. I mean, there is wine in Harvest Moon games. Wine is an item to buy in HMDS, and you can cook Wild Grape Wine. You can cook it in Sunshine Islands. 18 types of wine in Grand Bazaar, along with Champagne, and Beer itself. 11 types of wine in Tale of Two Towns, and I don't know how many are in A New Beginning. My point is, wine is a decent sized portion of what you can cook in the games, so I think they should be implemented. I love the idea of having tea. I love tea.