It may be a nice opportunity to introduce your parish to some new settings that are deeply inspired by the Gregorian chant tradition, and that are composed in the Gregorian modes.
Here are three settings from Illuminare Publications:
A cantor/choir edition containing all of the Gospel Verses for the entire Lenten Season, in addition to an accompaniment edition can be downloaded for free at the Illuminare Score Library.
These settings can be found in the Lumen Christi Missal, and in other forthcoming additions to the Lumen Christi Series. You can learn more here.