Assuming it is hydraulic, a properly built circuit and pump should solve the problem. Extending (and retracting) without load have little to do with pressure, and more to do with volume. Ie big pump parts and big lines. The pressure required for the actual lifting has more to do with mechanical advantage. Its high psi at low volume to generate the forces required.
The thing just needs one expensive pump and line upgrade. Pre charging an accumulator near each cylinder would serve much the same function. The control strategy would have to be intelligent enough to make sure the accumulators were charged while humans weren't waiting.
Your complaint is similar to ones I've heard from delivery drivers that use a lift gate.