"At least she's catholic" says Tony about Blanca when Carmela calls her a Porto Rican...and what ever happened to AJ's filthy rich girlfriend of a few seasons ago? The one with whom he borrows Meadow's appartment?
I think the observations above are very astute. I can see Blanca, perhaps unwittingly, forcing AJ into coming up with more and more money and the only way to get enough will be some mob scheme that could go awry and cause him to be pinched or shot.
What if her son needs braces? As Richie Aprile says of marriage, "It's an expensive proposition".