We use the mizzen halyard, but it is cumbersome as you have to take down the mizzen first. I have ordered a Block with a center hole through the sheave, available from several manufacturer I will use that for the balloner halyard and attache it with a normal shackle but also with a dyneema loop through the block sheave, that will give me an extra security if the block or Shackle fail the halyard will still be held up by the dyneema loop.
As extra security one can have a sling around the mast .