As a GT owner, I can agree with you that the GT ride is VERY bad on our Australian roads. Even though the road may not look at all bad, the GT's suspension is easily caught out and will often bottom out with a resounding CRASH! The suspension must be bottoming out very easily and must be crashing on the bump stop limits.
This is annoying me so much that I have ordered and received (but not yet fitted at this stage) a set of Bilstein dampers and a set of Eibach springs for both front and rear. My car has done only 35,000 kilometres at this stage so I have decided to not replace the suspension bushes at this time because of the huge additional cost. I can only source PowerFlex bushes and they are VERY expensive. (Maybe I should replace the bushes as well - what do you think?????).
I have also ordered (and still waiting for) an aluminium engine guard to replace the original fibre one - this will give additional ground clearance I am told. This guard is available from email@example.com
but again, is very expensive, especially when you add in the shipping costs.
These new bits will be installed at my next major service when I will also be fitting a Q2 diff. The timing belt, idlers and tensioner will also be done at that time.
So, fingers crossed - I am hoping for a huge improvement in quality of ride and will report on my findings when the job is complete.