Should I retake my ACT?

Stats:
ACT: (31-comp,33E,34M,28R,30S) (single sitting)
SAT Subject Tests: (Maths 2 -800,Physics-800,Chem-800)
IB Diploma candidate: 41/42 predicted. Breakdown: Maths HL (7), Chem HL (7), Physics HL (7), English Lang & Lit SL (7), Geo SL (6), French B SL (7)

Planning to take Further Maths HL starting from next year. It is an extremely challenging course as among 1,5-1,8 million IB students every year only 200-300 students get 7s.

ECs:

-Peer tutoring program creator.
Me and several other classmates comprise a group of students whose mission is to help lower grades in their academic pursuits. According to this program, each one of us takes 2-3 students for tutoring in our best subjects.

-Peer tutoring program for charity.
We charge a small fee of approximately 2 dollars for 1 tutoring session. All of the money collected goes to charity.

-Peer tutor.
Have served as a peer tutor myself.

-Chess club co-founder.

-Swimming?
I swim 3 days a week for about 2 hours. However, I don’t know whether this can be considered as an EC activity.

-Writing for my school newspaper.

EXTRA:
I am an international student from a country in Central Asia. Only 2-3 students from my country were accepted to MIT in last 3 years.
I have been studying in an international school for only last 2 years. The language of instruction in my previous schools was Russian (grades 1-9).
Few possibilities for ECs in my school. Most of our students apply to colleges in Europe, where ECs are not that important.

Question:
I have a disastrous ACT score for colleges like MIT, don’t I? Is it a must for me to retake it, or can I just submit what I have? The problem is that I want to retake (or take SAT instead), but I am afraid that I have already spent too much time preparing (I have done every single practice test and read several prep books), and I can’t allow this to continue because I think it will hurt my IB Diploma final grade due to insufficient time spent on preparing for their exams. Provided with good Subject Tests scores, do you think that I score enough “points” on Standardized Tests section part of my application?