Hi, thanks for posting...
Overall you should have a fairly strong profile. Your strengths include:
-solid, reputable work experience
-Thai 'nationality' and international, NYC experiences
-demonstrated quant skill through your finance background, masters degree, etc
-potential for interesting stories, good recommendations, some extracurricular involvement
Weaknesses or challenges:
-GMAT/GPA are average-- not a weakness but just means the focus will be on the rest of the application
-important to make a strong case for WHY you need the MBA... given your Masters already and your goals, it certainly can still do a lot for you but be sure there aren't questions about how needed it is
-will be important to stand out by showcasing key leadership experiences and innovation; people and project management, over your 6 years of work experience
So glad it sounds as though you are doing better physically now; what a scary and challenging disease you have dealt with! Hopefully you are starting a new phase of life and able to focus on the future now
..... b-school IS an amazing experience and a great chance to gain exposure to a breadth of skills, experiences, and industries within a short amount of time, setting you up with strong management and leadership skills.
Good luck to you!