I've used these grills for n years. I also cook only with charcoal/charwood. I use the bigger model with the smoker side attachment. That being said it's great for grilling or barbequing even without the extra fire box (which is expensive).
I cook everything you mentioned including ribs, plus also plenty of vegetables etc.
I would give up the smoker box willingly, but I would not give up the adjustable/removable charcoal tray willingly. It's way too useful while cooking, and makes cleanup a snap. I empty the tray into a metal bucket immediately after cooking and let the coals burn out there.