The mixer issue isn't so much digital vs analog as whether it can handle a hot signal, and I think most can. The Presonus Studio Live seems to have a gain control that can lower as much as -20dB, which should be enough (-13.5dB is what's needed). But I still think it's much easier to have an output module and not worry about any of this.
Your case is too small for the modules you have chosen (because you'll likely need more). You can do all right with a case of that size but it takes some experience to know what to choose for it, and even then, it will be limited.