The funding for this and all NASA projects is precarious. NASA's ability to execute on large, multi-year science project has also been less than reliable.

Roman uses an existing 2.4-meter wide field-of-view primary mirror and uses two main scientific instruments. The Wide-Field Instrument is a 288-megapixel multi-band near-infrared camera, providing a sharpness of images comparable to that achieved by the Hubble Space Telescope (HST) over a 0.28 square degree field of view, 100 times larger than that of the HST. The Coronagraphic Instrument is a high-contrast, small field-of-view camera and spectrometer covering visible and near-infrared wavelengths using novel starlight-suppression technology.

A study has found that the Roman Space Telescope will be ten times better at finding rogue planets. : The Astronomical Journal – Predictions of the Nancy Grace Roman Space Telescope Galactic Exoplanet Survey. II. Free-floating Planet Detection Rates
Samson A. Johnson, Matthew Penny, B. Scott Gaudi, Eamonn Kerins, Nicholas J. Rattenbury, Annie C. Robin, Sebastiano Calchi Novati, and Calen B. Henderson, 2020 August 21.