I'm not sure if you are looking for suggestions in general, but I'm not seeing any ventilation or windows in your coop. I'd recommend you be sure that there's plenty of ventilation as well as a way for natural light to enter the coop, and for you to be able to peak in and check on them without opening any doors.
I think the hydraulic springs idea is a good one. You might also consider cutting the lid in half, so you only have to lift one half of the lid at a time. There may e a thing or two you need to change in the way it is hinged and to make sure rain or snow won't leak in, but it might solve the weight problem.
I've been very pleased with the roost and poop-slide arrangement I set up in my chicken coop. It has made cleaning very quick and easy. Others have rigged poop-hammocks that seem to do a great job as well.