The first part is reminiscent of Romans 12:2 (τὸ θέλημα τοῦ Θεοῦ τὸ ἀγαθὸν καὶ εὐάρεστον καὶ τέλειον), and the last part seems to echo the Lord's Prayer in Matthew 6:10 (γενηθήτω τὸ θέλημά σου). So do you want to say "Let your good and perfect will be done, father"? That would be γενηθήτω τὸ θέλημά σου τὸ ἀγαθὸν καὶ τέλειον, πάτερ. However, the word εὐδοκίαν ("benevolence" in the unsupported accusative case) makes no sense in that context.