the 1/4"-connector could be used as a "line-level" input and the XLR-connector could be used as a "mic-level" input. Although such a use would be possibly considered to be "rare", it is nonetheless.....a possibility to accomplish!!!
Not rare at all - in fact, apart from most MOTU gear (with specifically designated inputs such as the Ultralite the OP has), and certain TC Electronic products, damn near ALL audio interfaces with XLR-combo input connectors have the XLR dedicated to mic-level and the TRS to line-level (going into the mic preamp via a resistive pad). Combo inputs that can also act as instrument inputs as well, have that side of things switchable (either physically or via respective the control software).
That's the case at least with Focusrite, Presonus, M-Audio, Alesis etc.