I did not interview at all three programs so I can't really directly compare. I think the call at IOL tends to be more humane than either UConn or Yale, I believe. Call is heavier (1st year is about q4, but weekday psych call is not overnight; 2nd year is 5 calls/month and again weekday call is not overnight) the first two years, but almost non-existent in 3rd and 4th year. Residents are a fun bunch, hang out together outside of work. I think, in general, IOL residents seem a bit happier than UConn. Lots of self-sufficient, diverse training opportunities at IOL, including research. Have C/L fellowship and child & adolescent fellowship.
UConn program seems to be more focused on public psychiatry, more biological. UConn is working on expanding some things in their program - just opened a child fellowship. Yale & UConn have the "university names" (although, in many psychiatry circles the IOL is well-known because it's one of the oldest psychiatric institutions in the country). Yale has lots of research opportunities and fellowships.
I think the three programs are distinctly different, so you just have to figure out what you are looking for in a program and see which one seems to be the best fit for you. Feel free to PM me if you have any more specific questions.
Good luck!!