When viewed through a generic, one-size-fits-all perspective, use of input enhancement does not appear effective. Through analysis of individual grammatical features and different learner proficiency levels, a significant impact may be revealed. To study the impact of input enhancement on diverse grammatical features, 16 short reading texts and writing activities (both timed) were given to a treatment group (n = 11) and control group (n = 9). While results suggest that average grammatical accuracy of the treatment group did not significantly differ from that of the control group (U = 11559.00; p = 0.30), input enhancement on individual morphosyntactic features yielded a significant result for the plural-s feature at (U = 122.50; p = 0.04). In addition to this less salient, redundant feature, input enhancement at specific proficiency levels appears to promote learner accuracy for some grammatical features. At CEFR level B1, for example, learners benefited most from input enhancement of grammatical features at intermediary stages of the Processability and Natural Orders of acquisition. Tailoring emphasis of grammatical features to learner proficiency during the communication process may foster greater accuracy.