I have a '93 320CE (correct designation) that has 205K miles. It is so quiet at idle I have glance at the tach to make sure it is running. Yes, 100-105 in hot weather is normal. You can get a resistor from J Forgione's website to bring down the temp (turn on the fans earlier) You mentioned a noise from the thermostat side. The AC compressor is in that area also. One of the things I always do on my cars is to have the AC compressor pulled and checked for the correct amount of oil. So far, I have never lost a compressor.
The biggest problem I've had is a strange limp home that only happens once in the morning and never again until the next day.
Anziani
'93 320CE 205k
'95 E420 125K