UCONN's CEIN has 4 campuses. From your school choices, I assume you live in the New Haven area. Could you live at home and commute to Stamford or Avery Point? Stamford CEIN uses Yale New Haven as a clinical site. Just a thought.
Of the choices you list, I'd definitely do Southern. You want a BSN. From what I hear, the job market is rather tight at the moment, and hospitals want BSN, not just RN. It's not so much about the quality of the instruction (the CCs turn out very good nurses; I don't know that much about St. Vincent's) as it is about maintaining magnet status.
I considered doing the CC RN route, but when I factored in the cost to finish up the BSN, it was going to cost as much as doing the ACE program at SCSU, but take longer. I have a bachelor's degree, but any school that's going to give you a BSN is going to require at least 30 credits be done at that university. So to get my BSN from WCSU (closest state school for me), I was going to have to take maybe two nursing classes and then a bunch of random classes, not because I really needed those courses (I have a ton of courses that could transfer) but just to meet the minimum institution credit requirements. Not worth it to me.
So then I was set to focus on Southern's ACE because UCONN's CEIN is about $10k more. Then my husband pointed out I could start CEIN in January and finish in Dec rather than waiting to start ACE in August and finish in July. His argument was that finishing 7 months earlier would mean starting work 7 months earlier (give or take, because I'm going to have to do a job search no matter when I go), and it's reasonable to think I could earn more than $10K in 7 months. So, although it seems counterintuitive, the CEIN program actually made the most financial sense for me.
If cost is your primary factor, I'm not sure why you'd look at St. Vincent's but not UCONN. St. Vincent's seems like a pricey way to do an associate RN program.