Anal hooks seem to be the new sensation. I have used both the one with a ball on the hook and the plain ones also. For the person doing the hooking, it's very visually stimulating....for the person being hooked, it can conjur all sorts of mindfuck.....however, the truth is that one must be careful....my subs are precious to me and perforating one's colon would be devastating for her and me.
Tying to their hair works ok, but hair does not stay tied well when the action gets intense. I prefer a "D" ring either on the gag strap at the crown of their head or on the back of the head harness that pulls their head back. I use a slip knot so that the tension on the hook can be adjusted. I have found that the hook is a great "predicament" tool that when combined with other action, it can distract and/or add control (both mental and physical) for the Dom. A subgirl seems to really find the idea of being "hooked" to be kinky when actually its just another anal toy. My take on tensioning the hook is that I insert the hook and get a feel for the tightness and flexibility of the woman's anus, then as I tension the strap, I watch for her anus to go from a round opening to a more oval shaped opening. once you have a fair amount of tension and her anus is oval shaped, that's about where you want to stop adding tension or pulling the hook.
The hooks I have used are usually 3/4" in diameter so most plugs are larger....the hook only enters about 4 " so most any other toy penetrates deeper....but the feel of that cold steel touching her ass crack all the way up her bottom and the knowledge that she is hooked really seems a turn on.
I have used the hook on a standing submissive, but never attached the hook to anything overhead or anything that might hold them if they fell or fainted. Instead with a standing sub, I connect the hook to a waist strap or elbows....somewhere on their own body so that if they fall, the hook falls with them and not actually hang them by their rectum.
one thing I found enjoyable was to use the hook in conjunction with a vibrator on her clit...the contractions of an orgasm are more pronounced and fun to watch...and...the inserted hook is small enough to also insert a finger up alongside for more stimulation.
Lastly, a hooked woman that is giving head and her dom cradles her head and controls the action transfers a lot of stimulation to her ass....very entertaining