TL;DR: (Full-pay) International student applying for Computer Science with International Science Olympiad medals but uncertain about how holistic admission works 
Stats
SAT I: 1600
SAT II: 800 for Math II and Physics
Unweighted GPA: 4.0
Weighted GPA: School doesn’t calculate, but I have a 44/45 predicted score for the IB Diploma
IB: HL Mathematics, HL Further Mathematics, HL Physics, HL Computer Science, etc…
Major Awards
Silver Medal at the International Physics Olympiad
Silver Medal at the Asian Physics Olympiad
Gold Medal at the International Olympiad of Metropolises in Physics
Common Awards
Gold Medal at national Informatics Olympiad (top 10)
Training team to represent nation at International Olympiad in Informatics this summer
First place in South East Asian Math Competition (less prestigious though)
Third place in World Scholar’s Cup Global Round Senior Division (a kind of debate / writing competition similar to the Academic Decathlon)
Some school level stuff
Extracurriculars
Physics and Informatics training programs (~10 hours a week each for two years)
School App Development - Lead developer of a mobile app for my school’s students, used by ~65% of student body
Research Internship - Worked with professor over the summer doing research in CS, unlikely to be published though
Leader of Math + Debate clubs / teams - Coach younger students in those subjects, lead teams to local and overseas competitions
Robotics Projects - Worked both individually and in teams to build robots to accomplish various tasks (e.g. solve a Rubik’s cube in under 2 seconds, play Flappy Bird indefinitely, stuff like that). I’m submitting a portfolio summarizing my favorite projects to MIT and CMU, and linking to it in the Common App additional information.
Miscellaneous volunteer work
Recommendations and Essays
My teachers are fairly experienced at writing recommendation letters for US applicants, and I’m fairly certain mine are strong. I’ve also gotten a recommendation letter from the coach of the Physics Olympiad team. I know I’ve been rated as “One of the top few I’ve encountered” 11 times and as “Outstanding” for the other four times, but I don’t know how good this is.
I’ve got feedback from a private consultant when writing my essays (so they aren’t terrible!) but the language / writing / voice / whatever is all entirely my own.
Where I’ve applied
I’ve gotten conflicting advice from my school, so I’m not going to classify these into reach / match / safety:
- MIT
- CMU (School of Computer Science)
- UC Berkeley (EECS)
- All other UCs for CS or CSE
- Cornell (Engineering)
- Georgia Tech
- University of Michigan-Ann Arbour
- University of Wisconsin-Madison
Questions
I know college admissions are random, but do you think I’ve got a shot at any of the above schools? I thought I was set for Georgia Tech and maybe UCLA, but based on the stats of people I’ve seen get rejected I’m not so sure anymore 
In particular, I’d appreciate it if you all could give me some idea of the probability of me getting into one of MIT, Berkeley, CMU, or Cornell, as I’d be ecstatic if admitted there. Also, do you think my lack of significant community service (starting a charity or similar) would be a major drawback to my application? I ask because I’m aiming to run a major hackathon-esque event later this year, and might take a gap year and reapply if you feel that including it would boost my chances.