You're on the right track. Now all you have to do is find everything the previous owner(s) fixed and repair them properly.
I didn't mean that to come off as an impossible task. I've restored quite a few machines of many types and I've found that the easiest way to deal with complex systems is to go through them and get all the settings and adjustments back to original configuration. Quite often amateur repairs miss the real problem and just counteract it by treating the symptoms rather than the cause. The nut in the pressure release is a prime example of this type of thinking.
Electrical systems are most prone to this type of repair but it extends to fuel and in your case, hydraulics.
If a taillight stops working the average fixer-upper runs a whole new set of wires rather than track down the faulty connection. I won't even go into what I've seen done to carburetors.
I had a class A motorhome that someone had completely rewired. They used green wires for everything. All the same dark green...