I see a lot of people complaining about corpse retrieval being impossible and I honestly don't understand what they are talking about.

When I was new to the game I entered my first swamp by boat and couldn't get a portal down before I was killed. I had to build 2-3 more boats until I could get a portal down and get everything back. I learned from that experience that portals should always be priority number one, especially when entering a new biome or making long trips.

If you have a portal nearby (which as just mentioned you always should have) you just eat some good food, get the rested buff + the corpse run buff, jump in your portal, sneak up to your corpse avoiding enemies, wait for your stamina to be full and then run to your tombstone, grab everything and get the hell out of there.

The only enemies you cannot outrun are deathsquitos but once you get to know them you can one shot them before they can even touch you. You just have to time your attack right. Or you could use bows from a distance.

If you are kinda new to the game, maybe you should avoid skipping multiple biomes worth of gear and food and progress more slowly. I know that there are people who play the whole game in troll armour but that's not how the game is meant to be played and an extra challenge those players chose for themselves.

I even stopped equipping secondary gear for corpse retrieval at all because all you really need is a nearby portal and enough stamina to outrun your enemies. A naked run also has the advantage that you can grab your stuff in one go without having to rearrange or throw stuff away.

For the resources I can only say that there are plenty for solo players and I would imagine even enough for 10 people but of course then you would have to explore and travel more to find them all...