I currently have a Nikon FM2n with a 45mm lense. Looking at buying either a Leica M6 or a Rolleiflex 2.8 or 3.5. I take landscape as well as portrait shots. My questions are: -Should I just get more lenses for my Nikon and if so, which ones? -Do I stick with my SLR instead of switching to a rangefinder? -If I purchase a Rolleiflex, which is the better model and lense I should be looking for? My budget is under $2000 for both camera and lense. Help!