Springs to open are a help to me and the less stuff sticking out to catch the thread loops the better. Nothing more frustrating then getting in t a good rhythm and snagging a wheel or clamp or bolt head or....
Here is mine, the base sites under my thighs when in a stool near the bench or the "tab" slip into a slot in a chair I modified if I want to sit in it for back relief OR the base can be clamped to the bench or work table - jaws swivel on base. spring opener with ratchet strap tensioner. ratchet it down at the lowest it can go and even that catches occasionally and I still mean to put a flap over it some day.
Made from oak flooring boards in a rush as a prototype and never felt the need to do another.