I'm a Spanish student so I'm going to put the adj. before the noun it describes. Not that that's at all your problem.
Don't change "mater" to a genitive. Unless context for some reason dictates that (in which case your adj. would need to change case too).
Being and adj. "eximius" also needs to match gender with "mater". It should read "mater eximia" or "eximia mater" (if everything is in the nominative singular).
Eximius
matris, mater matris, genetrix
Ecclesia Matris, or, since Latin word order is very flexible, Matris Ecclesia.
Oculi matris meae
lacta matris
eximius
Gift = Donum
deus caulum in oculus meus matris
Eximius Vir
The Latin word for Superb is eximius. The Latin word eximius is defined as extraordinary, excellent, fine, superb.
"Matris status."
eximia