While I am not a professor, and thus my opinion is uneducated, I can at least give it to you without wanting to die.
Technicalities
I believe that in essays you want to use formal language. As such do not use contractions. i.e. instead of didn't use did not. Also consider rewording phrasing that is less formal (I'm more iffy on this so figure it out yourself,) my suggestions would be things like:
- "... should have used his brain" > should have thought it through.
- "... just a little bit more digging" > just a little more research.
(Granted, you already used the word research in the sentence prior, and pointless repetition can be bad).
Grander Examination
I feel you might want to look deeper into the work so you are not just examining what happened. Think about themes and stuff. Think about author intent. Recognizing that this was meant to be experienced as a play can also be good. Heck, thinking about the time period can help with examining author intent as well! What you have here doesn't seem to really be going beyond surface level things, but I guess your main point of the Friar being responsible isn't really looking for deeper meaning anyway.
Granted, you are writing it for 9th grade, so I definitely think you can get away with what you have here, heck it doesn't look bad to me, but trying to push yourself is probably a good idea. I believe taking some risks and being more out there won't hurt your education (as later year's exams are more important?), but you'll know better about that than I.
Can you ask your teacher for feedback? I know some teachers are happy to help their students, just ask Gower! Would probably give you feedback if you were taking one of his classes. Also see if there is a criteria.
Depth
It might just be me, but think about if you are going into enough depth with your thoughts. Leaving things unsaid can be pretty bad, but you also obviously don't want to ramble either. Just... when you are proofreading, see if your point is fully explained, by asking 'why'.
"The Friar could have publicly announced the marriage of Romeo and Juliet, which would have forced the feud to halt then and there, instead of allowing it to snowball into a larger conflict later."
Take that as an example. It is a pretty bold claim that announcing the marriage of Romeo and Juliet would halt the feud. Why exactly would announcing it stop the blood feud? Wouldn't the parents just be pissed that their children went and married their enemies behind their backs? Like, you can argue for it, sure, but I think going just a little bit further into your reasoning might be good.
But do think about this yourself, because again, you don't want to ramble, and the length does seem pretty decent already.
Conclusion
No mention of the author's potential intent, play message/meaning, themes, etc. You are just trying to claim that the Friar is responsible, so it might not be needed, but having even one paragraph on how Shakespeare is making a point about society by having the Friar be guilty might give more variety to the essay while also showing greater understanding.
Obviously tho, showing that you understand what happened in the play is important too.
I'd ask a teacher for feedback (assuming you can) and also look into the criteria sheet if there is one.
Personally, I don't think the essay is bad, but it isn't exactly anything new or highly impressive (tho I may just be too harsh). However, if you stick with this, I'd be shocked if you don't get at least a decent mark.