The most likely resource(s) that would draw them to establish a permanent Vinland colony would probably be the same resources which dominated early New England trade: cod (and to a lesser extent, possibly, timber).
RE: OP, There are several large hurdles which need to be overcome to make a permanent Vinland colony:
- Getting enough colonists over for a sustainable population (which can withstand pressures from the, at the time, numerous natives)
- Allowing colonists from ethnically diverse (non-Norse) origins (again, helps grow and stabilize the population and provides incentive for other European nations to pay attention to the New World so that if one nation collapses the colony(-ies) may receive support from others)
- Surviving Christianization
- Making life there profitable enough for continued support and contact from Europe through the "Little Ice Age"
- Withstanding the Black Death even with continued European contact
- Probably a few others I am missing off the top of my head
Now, since the question seems to be more about what impact a permanent Norse colony on the N.American Continent would have, rather than
how it could happen, I would like to consider what N.America and Europe would like but really it all depends on the "how" so I really can't even fathom what would happen. Give us solutions and we can work from there.