Congratulations on your admits!
That's awesome you got money on top of the tuition. That is rare! Congratulations!
It is a tough choice. I think Darden has some nice benefits and unique features including case method. Usually it is something that either attracts people or turns them off. I would almost consider that above all else since it is the easiest to differentiate. Also, UVA Charlottesville is one of the most affordable places to live (though at the cost of one of the hardest to get to). I think many schools are pivoting towards tech, including Darden. Their bread and butter used to be high-flying finance such as IBanking but that has been drying up a bit.
However, in terms of networking, on campus recruiting and tech, no school can rival Kellogg. They get tech done really well and have 2 tracks - Product Management and Product Marketing for Tech. No other program offers that or even makes a distinction and there is a distinction between the 2. Your on campus recruiting will be much stronger as well (few employers want to get their butts to UVA - sorry).
At the same time, you are likely to leverage your military network in companies, on campus military club, etc. Often military folks are the first ones to get a job because of the network you have for life. Thank you for serving and dedicating your time - I think you totally should get the first dibs. I also know many military grads are very resourceful and don't want to overpay for the same thing if they can get it cheaper and I understand allure of not having to spend $40K to live in Evanston and graduating with $80-100K in debt. I think you can totally get the job done with Darden as long as you are ok with Case method.
On the other hand, if you are recruiting, people often want as much firepower as they can muster. It is good if you can overwhelm the enemy vs. showing up with just 1 more guy than the other party. The other benefits you will get is caliber of students, professors, breadth of recruiting opportunities on campus as mentioned, confidence that comes going to an M7 program and knowing you are the big dog.
It is a very personal choice. I could not fault you for picking either. I think there is safety and freedom in not having any debt and there is opportunity and a bit of risk with the other. At the same time, not uncommon to get 50K sign on bonus + another 50-100K in the first year at MSFT or AMZN (of course taxes are going to half that amount) but you won't go starving is what I mean.