Aju,
The people who recommend you should know you well and be able to speak specifically to your strengths and accomplishments. Thus, it is important to get recommendations from people whom you have worked closely with. So the other consultant and the founder of the start-up sound like good people. The professors from college would be great as well if again, they know you and you have worked closely with them.
Unfortunately I can't help much about how to portray yourself in the application process. My only advice is to be open and honest during the process, otherwise the admissions will see right through you. They get thousands of applicants a year and I think that they are good at sifting through them all to find who is the real-deal and who is a faker.