I’d be interested to hear if anyone has experienced any advantages from props not usually thought of -for example- mula bandha hanging by gravity boots or a massage vibrator on particular points, say where the elbows go in the Peacock. I love my exercise ball and that has many applications, can I hear some of yours ?
Funny that you mention gravity boots. I own a pair of them, and a long time ago before I ever tried yoga, I used to hang upside down for some minutes when I came home from work. It was quite refreshing actually.
Yesterday I was thinking about a good place to place a bar in my home, because I was curious what it might bring in combination with yoga.
I need a horizontal bar more than almost any other material object. The 1st thing in the morning and as soon as I come home- I hang loose. After some time getting my tendons and small muscles attenuated to the direction etc. I get an instant bunch of cracks that put me right- and in my case right means putting my 2 herniated disks where they don’t give me any bother. It even has a scientic name- Brachiation - and the Israeli Medical Assoc. did a study and found that brachiation alone increases bone density significantly. I feel it’s being true to our physical selves as primates. Our arms were built to hang. I don’t do the upside down very often but every now and then and it still feels wonderful. Namaste
" After some time getting my tendons and small muscles attenuated to the direction etc. I get an instant bunch of cracks "- There Time means in months and years past , not at the time of cracking- then it’s instant
I relied on blocks against the wall to assist with back bend wheel. Helped a lot opening my shoulders and chest. Now I can get up without it. Also, I cut a tennis ball in half and cupped the halves in my palms in downward dog. I found that it helped me rotate my elbows which pulled my shoulders apart and open.
I’ll try the tennis balls- In my avatar the photographer left out me barely touching the pinkie of my 87 year old Mother- I need the slightest touch to maintain balance, but I need it-and even if I didn’t I’d use my hiking stick because with it I’m able to twist and hold the twist. I sometimes use the stick to push further into my King pigeon as well.
And the Gravity Boots are great for abdominal-Pelvic work, for example the psoas.
Now I really need a horizontal bar! 
Can’t find a suitable place for one. So I need to get creative.
I have one of those that you can put in a doorway. Works great and has for many years.
I also use a thickly corded looped rope over the horizontal bar- I hoist a leg up and do cobra with the hands held high. I’m thinking of getting a longer rope to help get me up in locust.