I have not read all of the responses above. It sounds like you want to move into maternity and newborn photography, and possibly other people/portrait photography. For that, the advantages of a full-frame camera are several. I prefer FF over APS-C because of the way lenses function on FF. A 50 is a 50; an 85 is an 85; a 135 is a 135--at traditional distances, and in real-world locations. With an APS-C body, the 85mm prime is basically USELESS indoors in normal homes and smaller studios, except for TIGHT head and shoulder shots. So, seriously, forget the crop-bodies. And forget the 7D; its sensor performance is just average now, and its biggest issue is its weak color saturation and poor dynamic range. Ask a dual owner, like Buckster, how the 7D stacks up against the 5D-II. I know, I know, I know...7D owners like their 7D's but the fact is, the sensor is now old, and is well,well behind the times. THE BODY and its sub-systems are good, but the image quality, especially at higher ISO's, is sub-par by FF standards, and by the standards of the newer Nikon and Pentax crop-body cameras.
Prime lenses...okay...the 35/1.4-L...nice lens, but you pay a lot to get not much. Why not just the 35/2? And, if you have a FF body, you will need an 85mm/1.8. As far as affordable FF bodies, the 5D Classic performs quite well, still. Why? LARGE, high-quality pixels make it perform well at higher ISO levels (Better than the 7D by a significant margin), and it has excellent color quality and color depth. For a person who wants to do mostly portraiture, the color depth the 5D offers is an important advantage, and the 5D Mark II really is not much of an advantage, and is basically the same camera, with a few extra "invisible" AF-assist points thrown in, but otherwise the same camera as the older 5D Classic.
I would spend less on cameras and lenses, and more on lighting gear. Hence the idea of the 5D Classic over the 5D-II if you're just getting started. Portraiture is more about lighting and light control than about fancy cameras and lenses. High-speed lenses like 35/1.4 and 85/1.2 bring almost zero to the table when you're shooting with flash at f/8. I honestly would ADD THREE, or FOUR flash heads, and honeycomb grids, barn doors, and diffusers for at least two flash heads reflector sets (ie, two matching grid-barndoor-diffuser sets for two lights), a strip box, a boom stand, a portable backdrop stands-and-crossbar set, and two Lastolite Umbrella box umbrella boxes.
Right now, I do not see the 5D-II as a good investment; it is due for a refresh, and when that happens, perhaps Canon will finally make a camera that can compete with the Nikon D700 in terms of features and focusing and rapid handling; the 5D series has only middling to low-rent autofocus; I expect a 5D-III might actually not happen, but a NEW, finally-competitive body will take its place to compete with Nikon (and Sony! Happy guys??) head-on.
