Hi, I wouldn't describe the hatch opening mechanism as 'overly complicated' as it does tend to be a bit basic really. But, that said, it does suffer from wear and tear quite badly. The motor rotates a cam that has a wire loop on it. This simply provides mechanical assistance to the pawl opening mechanism, so at that point it is very similar to the purely mechanical early version. If the motor operates it could be that the wire loop needs some adjustment as the wire has stretched. However, do not be too enthusiastic here as if you adjust this too tightly the motor will jam, or simply snap the cable. As mentioned above, the rods might need adjustment to open the pawls fully, or the pawl mechanisms might be simply gummed up with muck, rust and general gunge. Taking them out and giving them a really good clean and re-lube with grease can work wonders. Inspect the hatch pins too, as wear there can cause them to stick, or if they have been adjusted incorrectly and are too tight in the pawls.
Remember that the hatch mechanism was never really designed to fully open the hatch, simply release the lock (pop the hatch open), even a new set of struts generally fail to open the hatch fully straight after it has been opened.
Spending some time servicing all the component parts and replacing the worn ones will (hopefully) get you back an operating hatch release..

. Pawl adjustment can take time, as it is not easy to line everything up quickly, but patience here will pay dividends!
Best of luck!