I have an old spinnaker pole I'm about to cut down to turn into a bowsprit, more than happy for you to take the excess which will be about 2.5m and turn it into a pole or a bowsprit yourself..
Yes. However what will effectively become the leech may be overly long (unless its a smaller spinnaker) making it awkward to get a good sail shape for some wind aspects. Conversly you can carry an asym on a spinnaker pole especially for going downwind (same issue as above but with the luff).
yes we do it all the time when cruising as it saves having to get all the sheets reaved and kites are easier to pack than headsails .Just run it off a purchase that tacks to the anchor roller usually pull it down fairly hard when shy and ease it off a lot as the wind squares up stick with the normal rule of keeping the clues level and moving the sheet car forward as you run deeper this will work from 10 deg forward till you get to about 30 deg aft of the beam then the pole becomes necessary as you shadow the spinnaker to much with the main had a look for a photo of sailing like that but couldn't find any sorry
