Hey bud! Its a strong profile. I'd just cut through the fluff which you'll hear a lot here and there from consultants or even seniors for you to have a clearer picture.
645 FE is decent, if you got a lot of time then I would suggest a retake. Its Feb and you plan to apply in R1, you can fit in another attempt but I wouldn't highly suggest it coz 645 puts you in the competitive zone already. Depending on profile clarity, we can discuss this in-depth if you wanna give a re-attempt or not.
Coming to your profile, I think it's strong but you gotta highlight your X Factors. For instance, I would suggest making your startup experiences heart of your CV. Academics might not be the strength but your diverse experience along with EV role can be great. I also have a plan for you to offer entrepreneurial direction to your profile too. I am sure you can build something (even, on paper) of your own in the coming months and presenting them if done aptly, can put you in the selection list irrespective of your GPA or GMAT.
The entire idea is to be unique and from basic understanding of your profile, it won't be tough to do that. Tepper and Cornell may be a little tough to predict, but if we follow our story strategy well for the other two, I have a strong feeling you can make into both.
Lemme know if this helps or if you can offer more insights into the startup experience you got, we can discuss it deeper. I see strong potential in you so feel free to DM in case you wanna get an in-depth evaluation too.
Cheers!