Whether it's film or digital, the key points should be: ability to change lenses, ability to set manual controls instead of just automatic and the ability to use a flash unit on the camera (not built in)
Considering you know how to handle camera , I , being very professional photographer from INDIA , only says that IMPORTANT features of camera are as follow Aperture , Shutter speed , Focal length & depth of field which make a good photo
Your lens is the 'make or break' of a good camera, and what kind of work your lens is being put to. A wide-angle or 'fish-eye' lens is OK for effect, but can be over-used. A 200mm lens for distance work is enough for most - unless you're paparazzi looking for royals to take 'topless' pictures of - and a 58mm 'portrait' lens is a must for taking closer up. A 28mm lens could be useful for architectural work where you need to get the whole front of a building in one shot, but not much use for most purposes except closer-up close-ups, taking 'pack shots' for instance, or models (not the likes of Lena Hart or Anna Schilling, although experiment is always a good thing). If you're a sports photographer it always helps to have a long lens that fills a frame with the action - two footballers colliding near the goalmouth, an outfielder who's caught out the batsman. It's then that close-ups of facial expressions pay dividends, and fill the photographer's wallet!
According to my point of view, auto focus is the most important feature of a camera. As we keep on working with it, we come to know that auto focus is usually better than manual. Very professional photographers prefer to keep their cameras on auto focus.