I have an '09 Fuji Roubaix with Tektro R350 brakes on it. I'm overall happy with the bike, but I'm not super happy with the brakes. I'm a big guy (~250), and the bike feels a little sketchy when going down hills. I'm not worried about the speed, but I'd love to know I can stop when I need to. I did replace the Tektro pads with Ultegra brake pads, but that didn't really make a big difference.
Does anyone have any recommendations on brakes for a guy my size that will noticeably increase stopping power? I have Tiagra brifters that I'm fine with. Should I just focus on the brakes/pads themselves, or do I have to focus on cables, etc. as well? I'd prefer not to replace rims at this point, but how big a difference would that make in the grand scheme of things as well?
Thanks in advance for any help/suggestions.