If you are going for true "JDM" look then the engine bay is supposed to be in primer shade only (unless the car is black or plain white) - e.g. in your case the engine bay should be plain white because you painted it pearlescent. Same in boot.
The 2 piece shaft is done for a neat package, its not the end of the world because you are not driving a truck afterall, Balancing the 2 piece shaft is a straight up PITA and requires a dynamic balancer to accomplish - It also means you have a center carrier bearing and an additional U joint. Your diff is fixed in place - this means the driveshaft pretty much remains steady throughout. No need for a one piece shaft - a live axle requires a one piece shaft ideally but as it is chunky and driving a hypoid axle it has to be lower slung - this creates clearance issues in a car e.g. older corollas. Yours is a bit better build.
I would suggest you use the original 2 piece shaft if its not damaged or worn. If it is then you need to find a "real" driveshaft machinist who can set it up for you with new joints.