If it ain't broke...
There are lots of posts about running temperatures and many responses indicate a general paranoia about it. I think that the feared head gasket failures make people take a belt and braces approach which could actually result in cars running at a temperature lower than that which they were designed for. Although this is unliley to have any negative affect, I believe that in many cases the changes are unnecessary. As long as you have a radiator capable of dumping enough heat and a working thermostat and fan switch then there should be no problems. Whether your car runs at 75 degress or 85 degress is unlikely to make any difference to the engine. If the manufacturer designed it to run at an average 85 then that will be fine. Radiator capacity is the most important variable - a lower temp thermostat won't make up for an undercapacity radiator, it will just delay the inevitable!
Yellow SL #32