The best thing I've done to my 2000TC is lower the CR from 10:1 to 9:1 (export TC spec). Before, there were flat-spots through the range and pinking under hard acceleration that was very difficult (and compromising) to dial out. Performance and rev behaviour is now much more like an injected setup - any revs, any gear, any gradient and it pulls smoothly and progressively up the range. Obviously, the revised carbs, induction and remapped distributor is the real cause of that, but the engine itself is now receptive to what those ancillary components feed it.
If this were Top Gear, I'd be labelled a fool. As we all know, according to the ancient automotive philosopher Clarksonius, the brake horse power figure is the most important number....in the world! But, as Graeme says, there are many more things you can do to extract a more meaningful and useful torque curve out of your engine, especially if you intent to use modern fuel in modern traffic conditions. 155bhp@5500rpm is all fair and well on the autobahn, but if you can't get out of the way of the turbo-diesel Fiesta at 20 mph, there isn't a lot of point in extracting it!
Michael