First of all applying at 30 is not necessarily a drawback. Although there is definitely a trend of applying at 27 or 28 years , schools still consider 30 years with 9 - 10 years of work exp for their full time program. And seeing your profile, I think you do stand a good chance in full time programs of some of the top B-Schools.
But definitely retake your GMAT in April to give your application an extra boost.
Not having volunteer type service experience is not a major issue. Instead you can highlight your hobbies or something that you are passionate about apart from work and how that has helped in your daily life can also be showcased by you.
I would suggest you to start early rather than wait. Finalize the schools that you would like to target and start working on their applications.
Feel free to reach out to know more regarding our experiences with candidates with similar backgrounds.
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