Wire on mine. Rope should be fine if you are still experimenting. However, be sure to use a rope with no stretch and no creep. Otherwise you will be constantly adjusting your halyard tension for the sail. Once you are happy with the length of the pennant, replace the rope with wire and you can then forget about it.
On my boat I have a furler so the halyard is a necessary part of tensioning the leading edge of the sail.
If I had a hanked-on sail I would probably invert the hoist arrangement to match that on my main. For my main, I now hoist the sail all the way to the top of the mast, and then tension the luff by pulling down the boom. This reduces the hoisting work on the halyard and puts the onus on the downhaul. I can use a multi-part block and tackle for the downhaul which makes it easy to adjust the sail from the deck and/or the cockpit. Plus I can just use my weight to push down the boom. A similar arrangement on a headsail would involve leaving the foot loose, hoisting the jib to the masthead, and then using a block-and-tackle arrangement to pull down on the tack of the sail thereby tensioning the luff.