judging from your description, one cause of hard starting is improper timing. An advanced timing can cause hard starting but a faster running engine. If you drive at high speeds, then having an advanced timimg is an advantage. Please check your engine heater plugs, it may be defective. If the heater plugs are okay, have the control circuit checked, it might be malfunctioning.
Now to your overheating problem, please have your radiator cleaned to eliminate the possibility of clogged radiator tubes. Check also your radiator fan. I hope these suggestions could be of help to you .
