Ditto every single thing you said. I think you may find some stuff easier with the CG between 4.5 and 4.75. I have mine at 5 now with no improvement over 4.75 but it is now unstable but manageable.
Mine will spin in either direction upright or inverted, but flat spin only in one direction upright and inverted. But thats to be expected because of "P" factor.