If you talking about a best job for a coach, it would have to Richmond. We pay really good money, have great facilities and literally you get probably the most negligible pressure and expectations to win in the entire league. As long as you tuck your shirt in and talk nice, you pretty much are good to go. If I'm a coach who wants to earn good money and not have to answer to a lot of demands that many coaches have to answer to, I want that job.
Now, if you are just talking about the best program in the league to coach, it is Dayton and it is not even that close in my opinion. Best arena, best fan base, best home court advantage, all of the resources you need to compete and you don't have the academic restrictions that some A-10 schools have. With all of those positives, comes expectations though.
VCU is up there, but their fan base is fickle (and has a size-able degenerate portion to it), they love their facilities, but lets be real, we call it Costco for a reason. SLU has an outsized opinion of itself.