This has been discussed here before. The obvious issues are the roller mast and no standing rigging. And don't forget this would most likely void your warranty.
Other than very light air the AI really doesn't need any more sail area. If I were to add a head sail for very light conditions I would lean more to a spinnaker than a jib. While you could roll a jib the extra limited amount of added sail area, IMHO, wouldn't be worth the extra work. Plus a chute would give you that extra bow lift the AI needs downwind. And a small jib is not going to give you anymore upwind performance to speak of.
Either route you need to make a choice: Sacrifice the roller main for a simpler head sail rigging, or design a complicated swivel mast head/modified main sail head to keep the roller main.
If I were doing this for only very light air sailing I'd sacrifice the roller main. If it's light the main is going to be all out anyways. I'd attach the standing rig to the mast head with something that looks like a sock with three lines attached. Low stretch line, not cable, for the rigging. The bow pad eye becomes the forestay mount (a pole or a sprit would be nice, and probably make for a better sail plan, but that interferes with the K.I.S.S. part of this route). The rubber ama handles are my chain plates. Tie a single block to the top of the forestay and run a halyard. The sheet blocks would probably mount to the outboardmost ends of the rear amas. Tie a bag on the foredeck or ahead of the mirage drive if there is room and you're ready to go.
A swivel masthead/shoud mount would require much more engineering/modification/money than I would throw at the AI. But hey, that's me. Some of you guys just love that sort of thing.
Any other ideas?