1969 273 upgrade advice

i have a 69 Dart custom LA 273 engine 3 speed auto tranny collum shift. Appears to have stock everything, so it's running the 2bbl carb. It has stock exhaust manifolds but each side runs straight back through a muffler and out the rear, I can tell the exhaust pipe is a lil bigger than stock as whoever put it on hammered it in a bit than welded it onto the manifolds. Anyway to my point, I don't want a race car but I would like just a little more pep in her step any advice? I'm not mechanically stupid but I am
New at this so any advice is appreciated for parts or whatnot.