Conventions: Stuff we covered already that I didn't kill you on, but I will next time: Contractions and past tense. You have to get these right. Some proofreading was poor - this is inexcusable and pretty much over forever in terms of your academic career. If you're not having multiple other people read your essays, you simply are not going to get this right (sentence fluency is also connected to this).
Presentation: Again, a no-brainer. There are many students in the C-B range that would have been in the B-A range had their conventions and presentation been on point. 12pt. font, Times New Roman, 1-1.25" margins all-around. Added for next time: last name/page # headers for pages 2 through X. Also, in-text citations will have to be perfect for our next formal essay.
Lastly, 4-6 means AT LEAST 4.
Add your concerns/thoughts in here if you'd like either me or your peers to chime in.