At lease it's evenly low. But you did heat the crap out of it. That probably did something to the pistons and head. Melted the valve seals or fused the rings to the pistons. It should be at least 120+ PSI dry cranking. If it was 70 then there is some major problems. It's fine to test with the plugs out. Does not change anything.
But you also say you needed to dump in a large amount of oil. I'm sorry to say it but I would rebuild it. Depending on your cash flow you might be able to get away with an Okey rebuild. Just drop in pistons and rings and run the crap out of it. Pick up another engine and build it up while killing off the one you have. But if you have the money then do it the correct way. Have a short or long built up for you.