fully agree with the "fettling is everything" notion.
Changing all the suspension rubber and bits often makes a huge difference - especially those rubber interleaves on the leaf springs.
These cars were carefully designed "of a piece", and all the parts have to be up to snuff to get the right feel. Usually takes like a year or two to get this stuff all done, even after the car is a good clean runner!
100% agreed changing all the rubber bushes, engine and gearbox mounts totally transformed my Fulvia.
Not a cheap job as the bushes and mounts cost £680 but well worth it and a big shout out to Omicron for a great service.