My 2000 TC was lacking low end torque. I would have to change down a gear earlier than I used to. The solution was to adjust the valve timing with the vernier adjustment. This adjustment is easy and is described here (as a stick thread). I would check valve clearances while you have the cover off, and adjust those if needed as well.
My other suggestion would be to disconnect the fuel line from the carbs, and briefly, and not in the presence of smokers, turn on you ignition and make sure you have a good fuel flow out of the line. It should squirt vigorously. If your fuel lines are clogged with rust and debris then you will have fuel flow problems even with a new pump. If the lines are clogged with crap, then you should also inspect the fuel tank, it may be rusty.
Also check under the car and see if there are any inline fuel filters installed that need replacing. There might be one from a previous owner that you do not know about.
My 2000 automatic likes to run best on the reserve fuel line. There seems to be some constriction in the main line. Have you tried both fuel lines. Also is the main reserve fuel valve opening and closing all the way?
James.