I hope I'm not alone when I say that I'm frustrated with Henry Gale being a very lonely unexplained event in the island's history. Especially considering all this recent talk about Jacob bringing select people to the island and that everyone who can find the island and land is chosen for a specific reason, it seems odd to me that Henry Gale has only served as a vehicle for some dramatic action in the final episodes of season 2.
There are certainly bigger and more important issues to handle in season 5- not saying this is essential. Part of me understands that we'll probably never get to see the circumstances surrounding Henry's landing and eventual death on the island- but even just one more small ode or reference to his story would provide some sort of healthy conclusion for me. I think it would keep Henry's little story from being just a little blip during season 2- it would hold more meaning. I'm not looking for an explanation even, just more relevance to where we are now in the story, similar to the drug plane, which has had a healthy life throughout the series.
I think if there was ever a time to do it, it would have been during the time flashes. During the trek to the Orchid, in between those two flashes that happen very close together, I would have loved to see a disorientated Locke gaze up into the sky just in time to see a big smiley faced balloon passing overhead. He could have even uttered the line: "Henry?" just before the next flash occurred.