Different aircraft require different lift off techniques; personally with a 152 doing a normal (flapless) takeoff I prefer ( and it is my personal preference) to pull the yoke back just slightly aft of neutral as I begin to roll and the aircraft will then lift off when it is ready.
This.
For sure a small elevator deflection just changes the angle of attack, while a large (but not enough to stall) deflection results in a loop, or at least the beginning of one. Wonder why?
Not really. The elevator deflection required for a loop entry would likely be less than that applied to raise the nose for takeoff. It's the "entry speed" which differs. If you applied the elevator you would use during takeoff at the entry speed for a loop, you would damage the aircraft.
For my 150, and most tricycle aircraft I fly, I will apply and hold full elevator up, and if a crosswind, full into wind aileron, and hold those inputs until the control affect begins (speed increases control effectiveness) and then I will relax the controls toward neutral to maintain the desired aircraft attitude.