I cant speak from experience on the drifter but my preference is the a sail because:
1. The sock makes dousing single handed very simple.
2. You can sail deeper downwind with an A sail than a drifter in light air. Drifter gets blanketed by the main much easier.
3. The A sail will go up to 60* apparent in light air, plenty high for me.
4. no hanks or wire to deal with, just stuff the whole mess in a bag never gets twisted in the sock.
5. I have an A sail I would have to buy a drifter
Alas no photos of the tack line set up but i will try to describe. Starting aft attached to a stanchion base is a single ratchet block with a cam cleat. The tack control line runs forward through this and several other blocks. near the bow this line goes through a 3:1 using a single with a becket and a single attached to a stanchion base. The single with the becket has another piece of line attached to it that runs forward and through a single attahed to the anchor roller then up to the tack of the kite. The 3:1 has about 12' of travel so the tack can be eased way out when sailing deep helping the luff to rotate to weather and sinched down tight when we need top point with the sail.