Getting clogged might or might not have anything to do with the toilet. Theoretically, nothing should have happened to your toilet to change that. If it clogs, it's probably because something down your drain line is partially clogged. That could also affect the "flushing power". I'd address that first. As long as the tank fills up (look inside to check), and the water goes into the toilet when you flush, there's nothing much more the toilet itself can do.