I'm one of many people who at various times got to spin the Bloodnot at Sunny Boscombe when it managed to scare a few more students or QFIs.
We always decided it was basically friendly, but did have a definite potential to frighten. I can't recall any tendency to spin of a manoeuvre either. The particular mode of rudder-induced high rote is new to me, but the elevator relaxation problem (or moving the stick forward too slowly during recovery) was a known characteristic.
The standard way to create a high rotational spin was about ½ in-spin aileron during the spin. The high rotational spin was always recoverable but could take a couple of turns, and never gave warning - you have to hold the recovery controls on until somebody belts you in the side of the head and you know it's recovered (often the lateral g on recovery tended to destroy vision for a couple seconds, which was entertaining).
If you've got the Lycoming inverted oil system mod fitted, the oil pressure drops to zero or thereabouts during the spin as well, which isn't inherently dangerous but bears keeping an eye on and can increase fuel consumption a bit.
We never felt the urge to try inverted spinning, so if you intend to try that you will be turning very quickly into a test pilot. Personally, I'd advise against it.
G