dicho, i think the problem with the wic=creek etymology is that the Old Friesian and old English words for these unwelcome tourists(wicing/witsing/wising) seem to come from words meaning either settlement or temporary camp: the "creek" meaning came much later in Scandinavian languages.As you say they all derive from the same root and mean many things in many Indo-European languages, generally variants on"places where you live": in various languages at various times this can be house, group of houses, village, camp, inlet etc etc.Given contemporary and archaeological accounts of how the early Viking raids happened(they wouldarrive, throw up a temporary wooden camp on a peninsular or similar defensible position, and raid out from there). The -ing ending means "people of" in English and Friesian at the time,so people of the camps seems the best bet in my book. But as you say, it's a lot of guesswork.
Anway, in the context of the general level of this thread I thought "camp" fitted in well with "vacation" and "tourist".