Choosing a part-time MBA program with good ROI

I am an IT management professional with 8+ yrs of work experience with substantial leadership experience & consistent growth trajectory in my profile so far. I am currently designated as an IT Director & Client Partner located in Memphis TN, and have been rated among the top 2% performers.

At this juncture of my career, I am considering a Part-Time or Online MBA option but need some guidance in selecting the school. I am yet to take my GMAT test but am targeting a score of 680-700+

Personally I have a very strong inclination towards the top rated schools like Chicago Booth, Kellogs, Kelly, UNC, Carnegie Melon, etc. However, considering my existing growth opportunities in the current company with a $90+K compensation, will there be an ROI of shooting for the top schools spending $100K+ tution fees or should I rather settle in for a decent school within the $40-60K range?

Its not that I am not open for changing jobs after the MBA, but so far I have had good growth this my current employer. I am not being able to decide between a ranked MBA with huge tuition fees v/s mid-ranked MBA with affordable expenses. My current employer does not have sponsorship policies, so the expense is definitely a factor for me. But at the same time, I do not want to make a mistake in judging the best ROI for my career going forward.

Any guidance will be highly appreciated! Thanks in advance!

(29 Yrs, Female, Bachelors Degree in Computer Applications, Strong Extra-Curricular in Art & Culture, 4 yrs of Volunteering Exp, Strong Prof. Recommendations)