I'm not up on Australian history and I do not know how many people this would cover but my guess is that the scope might be too narrow for a full-on 'project'.
Regardless if a project is merited or not, categorizing would certainly be appropriate. When you are making categories try to capitalize on the fact that you can make a 'spider web' of categories and sub-categories so people can 'drill-down' to your info following different 'paths'.
I don't have the subject knowledge to give good input on the exact break-down but I'll throw out some very rough ideas to try and give you a creative kick-start. You'll need to use your subject knowledge to figure out what is the most sensible organization and category names.
[[Pioneers, Kangaroo Island, AU]] *maybe a sub-category of [[Arrivals_to_South_Australia]] or [[Australian Immigration]] and [[South Australia Company 1834]] and [[Kangaroo Island, South Australia]]
[[South Australia Company 1834]] *sub-category of [[Businesses]] or [[Organizations]] and [[Australian History]] and [[Australian Immigration]]
[[South Australia Company Ships]] *sub-category of [[Ships]] and [[South Australia Company]]
[[SAC ship, Duke of York]], [[SAC ship, Lady Mary Pelham]], [[SAC ship, John Pirie]] etc... *sub-categories of [[South Australia Company Ships]] and [[Pioneers, Kangaroo Island, AU]]
[[SAC Company Officers]] *sub-category of [[South Australia Company 1834]]
Then the individual people can be categorized by the specific ship they arrived on, and as a pioneer/settler of Kangaroo Island, and (if applicable) as a company officer of the South Australia Company.
If you (or someone later) wanted to, for example, provide details about a specific ship then you can add it to the category page. So the Category [[SAC Ship, Duke of York]] might point to the wikipedia article for [[Wikipedia:Duke_of_York_(ship)]] and give some basic details: Launched in 1817 she was first used to carry settlers to Nepean Bay Australia. This was her only succesful voyage as she was wrecked in 1837 near Moreton Bay, Qld, AU on her first whaling voyage.
Also don't feel you need to do all the categories and sub-categories first - you'll probably feel overwhelmed if you try that... choose a start point, so if the idea of listing the 38 passengers of the Duke of York under a category for just that ship makes the most sense just create that category and make it a sub-category of Ships for starters - it can be changed later. The only thing you should consider a MUST do is to come up with a concise, unique, meaningful but manageable category name. [[Category: Duke of York, Kangaroo Island Pioneer 1836, South Australia, Australia]] is just a little long making it prone to typos (or you'll be forced to copy/paste it everytime you want to use it)