I actually had a '97 eagle talon before my VX. I lost it an accident in february. I loved that car...but you always love your first right?
If the shop has done all these repairs, don't you think they would have done a pressure test that could determine if there is a blockage? Is this the 2.4L 4 cylinder or the V6/GT? You could always use Red Line's Water Wetter fluid mix. It increases the heat capacity of the water.