If you could only do ONE exercise, is there anything superior to the squat-curl-press?
It is the superior compound exercise, working every single muscle. Even if you only use two 40lbs or 50 lbs dumbbells, that would be enough to stay in shape. You wouldn't get huge, but 3x30 squat curl presses of 100 lbs a day wouldn't be bad.
The objectively most efficient compound, if you could only choose one, would have to be either the clean and jerk/clean and press or the deadlift. It needs to have a good anterior/posterior balance.
Squat-curl-press is shit. You would never be able to do heavy weights.
Clean and Press is a much better one, or Clean and Push Press.