The seventies is not too bad in the overall scheme of things. Glad to hear you are getting some relief!

Almost all refrigeration calculations for load and dissipating that heat loads are done with a temperature change of 30 degrees of change. This is BTU's removed, Of course,it is a rule of thumb again. You can also use a rule that the refrigerant temperature at the suction valves will approximately 10 degrees colder that that outsides of the tubing on the evaporator.

Actually when it come to air condition say like malls and stores they do not want people to walk in from outside and be subjected to more than a 30 degree change of temperature.
Air conditioning means to condition the air by cooling, heating, humidifying, dehumidifying or filtering.

Air temperature change can cause people to faint coming in or going out.
People with blood pressure issues whether they know it or not can find it out the hard way. If you think about it, that is the number one reason ambulances are called to malls in the summer time. People are usually there for coolness on the cheap and are older or less healthy because their bodies respond slower.

If a car was as cold as you think you would like when you pop the door you could almost feel a your breathe being taken away because the hot air is naturally thinner air!
This stuff is a double edge sword, literally!
Cold conditioned, refrigerated air can also be lower in humidity. When you open a door and there you are to deal with hot humid air, like in the south east.
You have no perspiration on the body to prepare you for the sudden change in heat. you have no cushion to start keeping you cool and if you are person that is slow to perspire, then, there you have an overheated human.

Work on the other things I mentioned and you could decrease the time to do a cool down. Thecompressor will work less and save you some gas, it is the theory anyway!

Phil