If you are looking into big 4 public accounting region, there is absolutely no chance that you will be hired. Top accounting program does not really matter- what matters is whether your school is good enough that big 4 would hire from there. Rest is your GPA. I believe our office look for at least 3.5 due to higher volume of application. Your best bet is to get M.Acc and get your GPA polished.

I understand how you feel- I had 3.0 with B.A in Economics and had some shitty regression modelling jobs. Hated it, so I went to M.Acc and worked my ass off.

Lastly, I think you need humbleness. The person gave you a job - surprisingly, it is lot more than average A/P, A/R clerk would receive. They understood that you were overqualified, but they liked you enough to offer that much to have you work for their firm. I don't know about you, but I'd be real happy if I were you. In Midwest, big4 brand new hire gets paid 50k. 45k is 90 percent of 50k and I am sure that there wouldn't be too much work for A/R, A/P. Had I not enjoy learning various industries, I would have taken corporate job without hesitation.

most everyone else there doesn't have a degree at all, except for my supervisor and his supervisor.

This threw me off really hard. Degree doesn't mean jack on the face of experience. You SHOULD NOT judge people based on degree. The tax corporate manager with high school diploma and 20 years of experience whom I work with schools my ass every time. He worked his way up from A/R, A/P clerk and is very knowledgeable on his subject.

All in all, if you believe that you an move up in ranks fairly quickly, take the job. Most of public accountants are going through crazy seasons to move back with higher rankings in private industry anyway.