I haven't been to La Hacienda for Illuminations so can't answer that specifically. Most Epcot restaurants have only a few, limited no of tables near the windows so it is a lottery of chance whether you get that coveted table. Many of us believe that it is better to stake out a nice spot around the Lagoon for Illuminations rather than book a restaurant hoping to see the show with dinner because 1) there is no guarantee that you will actually get a window table 2) even if you get a window table, chances are other diners may well get up and crowd around you at the window to watch the show and even block your view and 3) the best views are still typically outside around the Lagoon. If you love the menu, are excited to eat at the restaurant and just consider Illuminations to be a nice possible only bonus (if you are lucky to get a table at the window), then go for it. But if your main purpose is to see Illuminations, then eat earlier (at any restaurant of your choosing) and then grab a nice spot around the Lagoon. There are some good spots eg on or near the little bridge to France, around the Italy boat dock (but you then must choose to either battle the crowds on the long walk around the Lagoon or duck into some shops or a bar to kill some time & wait out the stampede to the front of the park), or on the landing/balcony at Tokyo Dining in Japan. I'm sure others can add more (and much better!) to the list. Sadly, WDW promotes some Epcot restaurants with the hook that you can dine while watching Illuminations. That isn't always the reality.