I would say at 36K your shocks/struts should be fine.
KDW's are a loud tire when they wear, I have found out from a few friends that got them and now they are getting louder as there life cycle ends. And they are a sticky tire that would get chewed up easy. Also same friends have torn up a set with just one or two trips to the track drag & road course.
Alignment would cause issues, are you lowered? The Toe in needs to be adjusted for the lowering. Do check the alignment at least once a year? I know you probably have now. But gotta ask the dumb questions
And how are your roads? I have learned since moving to Washington state that people run studded snow tires tear up the roads and my PT which was quiet in a relative way is now almost unbearble. Its not the PT its the roads, have been chewed up since I moved up here. It could be a compounding of your issue.
Tire pressure for the PT is a must on the check list. I have found owning two of them that they can be sensitive to it. Just a few PSI low and handling suffers. And with performance tires the tires themselves can be more sensitive to minor changes.
$700 for tires sounds steep? is that the same tire installed? I would shop around or search here and on ptcrew there are many tire threads about good tires and where to find good prices for them.
I hope some of this helps.