You still have plenty to work on with the Dart. You will be dickering with it constantly. It's an old car. When Hotchkis is done with there part of it, don't expect all of it (or any of it) to be a new car reliable.
Soak in driving and tuning on the Dart for a year. Then consider something else.
While you have some parts they are sort of incomplete or have issues (except for KH disk setup). So the cost associated with putting them in something is still significant.