It is hard to say. It has been ridden hard and literally "put away wet" as they say.
The cylinders' compression is within 10% of each other. The differences could just be carbon buildup and decarbination may take care of that.
One thing to be away of....the issues with the cracked head causes water intrusion in cylinders #2 and/or #3. It will show up in compression numbers and also water beads on the spark plugs. Of course, you will feel a miss in the engine caused by the water.
As for your oil problem....I do not think you will have to disassemble the powerhead to see what the problem is (although, I have been wrong before).
You will need to remove the powerhead, which takes a little time and care. You have to remove the lower unit, lower motor mount, mid section, oil pan, and disconnect much of the wiring harness and hoses around the power head.
If you are going to do this yourself, you should purchase the Honda Service Manual, so you have all of the torques and torque sequences in putting it back together. Also, take a lot of pictures, so you can put all the hoses and wiring back in the correct order.
Once you pull the powerhead and examine the oil pan, associated gaskets, power head gasket and more importantly, the bottom of the powerhead, itself...then you can make an intelligent decision.
Of course, if you are going to pay someone to do this, it might end up throwing good money after bad.
I do not this there is an easy answer to your question.
Mike