This study investigates the effects of teacher-focused feedback (TF) and automatic writing evaluation (AWE) on global writing performance as well as syntactic complexity, accuracy, lexical diversity, and fluency (CALF) of English as a foreign language (EFL) learners' narrative and argumentative writings. The participants were randomly assigned to TF and AWE groups. During the treatment, the teacher delivered instruction on the narrative and argumentative genres, followed by the participants' engagement in writing texts and getting feedback either from the teacher or AWE. The results revealed improvements in overall writing performance (formal aspects) as well as CALF measures. While there was no significant difference between the two groups in their overall writing performance, AWE yielded better scores in lexical diversity and syntactic complexity, and the TF group outperformed in fluency. Moreover, an interaction was found between feedback types (TF vs. AWE) and text genres in CALF measures. The narrative writings were characterized by higher lexical diversity, syntactic accuracy, and fluency, and the argumentative genre, yielded higher scores in syntactic complexity. The results suggest that both human and machine assessments were beneficial in improving written products in EFL contexts. Also, engaging students in writing various genres is likely to result in improvement in different CALF aspects.