which are going to be much less pronounced this far back in the past.
Well maybe in Administration but Transportation is still hundreds of miles above what the Natives can do. As for administration the more primitive system used by the Greenlanders and Icelanders would have actually been highly beneficial as it would allow far easier absorption and assimilation of native tribes.
By founding a settlement, you get to be the owner/lord of said settlement; it would then make sense for any natives that start to use Norse grain and livestock to come together and form a village with a chief that could easily be integrated into the Allthing without too much change in the people's everyday life.
I'm mostly talking about how they'd interact with larger, better organized tribes to south,
Fair enough.
such as the Mississippians or the Algonquians.
The Mississippians were disunited as well as archaeological evidence pointing to a very poor diet resulting in them having poor health and immune systems presumably resulting in them being shorter and not as strong as other Natives.
Besides the first part of the 'conquest' will probably be not through warriors but through missionaries. With a significant Christian minority in place assimilation is much easier or if the local leaders oppress any Converts or if any missionaries get killed those can be seen as decent casus belli. They probably would only take key Portage points or locations along the river at first and then probably expand from their.
As for the Algonquians they didn't really start their huge growth until the late 16th century with better agricultural practices. Even then their villages were semi-nomadic (similar to the early grain harvesters in the Fertile crescent funnily enough) and slashed and burned areas to grow their crops in for a year or two then moved on to a different location. In OTL this actually
attracted settlers as there was already clear land around here and there.
Either way, while the Algonquians could feasibly keep their independence far inland the Coasts and major river systems would most likely result in Norse settlement and when technology improves you could see an Ivan The Terrible Russia like situation with a large push inland to link the Mississippian settlements to the Atlantic coast settlements.
And considering the Norse liked money as much as raiding
Eh, the whole Raiding craze was dying out around the time Vinland was settled, Believe it or not by the time of Harald Hardrada the Viking age had been over for the most part for a few decades. Though when tempted by riches like the Spanish to the wealth of the Aztec and Inca even a culture that doesn't raid often will be tempted and if nothing else every country has the occasional pirate.
And a small exploratory ship probably wouldn't be able to do too much raiding but neither could it do too much trade either.
meaning the natives are going to pick up ironworking in fairly short order.
Okay it seems reasonable that Iron objects would be valued in Native economies yes? Then why on Earth would the Norse
help the Native start their own Iron working industries and loose one of their most lucrative advantages in a native economy? Yes it could be unintentional but given most people the Norse would trade with would be quite a bit away from their settlements and they could only get there on Ships then how would they learn Iron working from that?
A Native tribe
could learn it if they're close to Norse settlements(their near imminent assimilation and conquest aside); but then when they know it why would
they teach it to another tribe/clan? It's similar to the Chinese with Silk, sure the Koreans, Japanese, and Indians managed to get in on it but did they went out of their way to teach the ways of doing so to others? Not the perfect analogy but the basic idea is the same, and you can't stuff an anvil in a hollowed out walking stick

.
Sure you could say an escaped slave or something came into contact with a Native tribe and taught them Iron working but the likelihood of that is small (not too small but still small) and After a while there would be an 'inflation' of Iron goods after the Norse have been around for a while so they won't be as expensive as they would be later and thus less of a desire to do so.
Honestly they would probably be more interested in a Loom than anything.
At any rate, many native tribes used stone weapons against the Spanish when they invaded to a reasonable measure of effectiveness.
They used Obsidian weapons, the Aztecs used a deadly variant called the Macquahitl which looked like a cricket bat with slits in the side where flat elongated obsidian blades were stuck with pitch and wedges. It was said to be able to decapitate a Horse cleanly, interesting stuff.
But it's effectiveness was due to the Spanish not utilizing metal body protection as much as they used to given in European wars it wasn't as effective as it once was. Obsidian is far too brittle and would crack (it is literally a natural volcanic glass) leaving obsidian weapons edge-less. So whats interesting is this might mean that the Vinlandish could end up using chainmail or Lamellar as well as shields far into the 18th century or least some troops would.
This really depends on how long it takes for the Norse to "go native," as it were.
A mix of Norse "going native" and Natives "going norse".
I have to wonder how long the Norse will keep up the conquering
Depends on what the butterflies do. There's a chance if you want to be optimistic that they take all of the Americas Pole to Freezing Pole, though what I think would be likely is they take North America, the Caribbean, and good chunk of the Northern pat of South America. Everything south of that could be other European powers trying to gain territory. If you want to be pessimistic but still reasonable I suppose the regions of Canada and USA will be Norse, maybe not united but they would be Norse at some point.
honestly, since their modus operandi in Europe seemed to mostly be "seize a few sparsely populated areas, do some smash and grabs, and then do our actual job of being merchants."
Well it would be a bit different in North America due to them having such an advantage over the Natives (at first at least) as well as the land being so ripe for the taking and population pressure from Iceland.