Sounds like a lot of other cars. On subis we buy or make AOS's (air oil separators). The PCV systems let a lot of oil into in manifold which comes from blow by pressuring the oil pan during compression. No piston rings are 100% tight and some oil just gets sucked out along with the air pressure by the PCV (which is why they gum up after time). Subis also have the problem with the heads being on their sides and hard turns puke oil out the vents and into the manifold. A AOS can be routed back to the oil pan via the crank vent so whatever pukes out goes right back in after you slow down or stop turning hard. I never had oil issues as so many others did in stock form. I even have a 2013 dodge ram hemi that never sees above 3500 rpm or hard turns. I installed one of my AOS's on it and in 1500 miles had about 4-5oz of pure oil. I did not run the AOS back to the block on my dodge like I did my subi so my AOS acts more like a catch can and I can see and measure what the motor pukes out. I'd look into one if I were you and if it can go back to the block like subis run them. You shouldn't lose a drop if it can be done since this is where most of the oil goes. However some motors have bad piston rings from improper break in so it could be from that too. Again in the subi world a lot of guys where ok with like 130-140 psi during a compression test as long as each cylinder wasnt more than a few psi off of one another but the manual actually went up to like 150-173psi. You could check what nissan says the normal range is and check yours.
FYI, all performance motors I beat on them pretty good during their break in period using a method and I've never had oil loss issues. Keep in mind a crappy break in and poor rings will allow more blow by to enter the pan which means more oil will get sucked out the PCV system and oil will enter the cylinder from below so its a double whammy oil loss.
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