You might want to periodically walk in a straight line without needing to press the jump button, you might want to keep sneaking while you are in freecam mode, or you might want to use togglesneak for only some circumstances. If so, then this is the solution. I remember that in the older versions, you could get a boost in stair climbing speeds when you have autojump on, so these toggles might be useful for other tasks. I'd also love to freecam without the need to show my name plate or fall off a ladder.

Autojump is vanilla, togglecrouch is called permanentSneak and can be assigned a hotkey.

Why is being Vanilla a hinderance for adding a hotkey? You could make a hotkey that edits the options.txt file and applies it in game directly. That's exactly the gamma tweak does, and I'm sure you can do the same with Autojump. Also, permasneak doesn't work with freecam, and the vanilla togglesneak makes the freecam perspective continuously go down.