Almost no heat (if your heater core is hooked up) STOOPID stuff with the temp gauge, ie sometime hot, sometime cold, bouncing around, etc etc. Overheating for no reason, not heating up the next time for no reason. With me bro?
Another thing to keep in mind is the car's attitude towards coolant. I had a '79 F150 (351M) that would run forever with the coolant about 1.5" from the top. Fill it up, it'd puke it out, right down to that level. Found out, if it's happy there, then leave it alone. Just like women. HA! No, not true. Women are pink on the inside, and bitchy on the outside.
ANYWAYS, why do you have the fan coming on at 70*? Engines need SOME heat in them, especially if you have any "important" parts made of aluminum. 180*-200* is perfectally fine operating temperature. I'd set that fan to kick on around 120* or so. Is that your ONLY cooling fan, or is this an auxillary fan?