spawn-point

Spawn point is the location of future object/NPC/Monsters.
General guidelines:
Instance spawned object/monsters allow to fairly distribute stuff(loot/exp) and provide more of a single-player experience(i.e. Diablo-like multiplayer with small parties fighting through a dungeon).
In-world interaction is better suited for clan/faction warfare and sometimes PvP.
In-world farming of chests/boss drops should be regarded as design flaw that creates a bad impression to the players moving through.

Objects/Treasures:
1.The more "realistic" way to spawn objects is to spawn them when player is not looking at the area. Unless the population of the area is near-zero this won't work:
Why? Players camp spawn points, even in low-pop servers.
A.Instead spawn points themselves should be random and appear at "place where least players look"/least active zone. No static spawn points.
B.Spawn timers must be very randomized with long "drought periods". Unless you want every spawn of chests be opened by bots who monitor the entire area.
C.Spawn points can appear at future path of walking player to draw attention quickly. This allows "stealthy redistribution" of treasure chests towards active, non-bot players using some form of resource allocation e.g. 1chest/player day, this amends some of the issues with chest-camping and bot farming
D.Also consider daily awards from vendors/mail instead, i.e. just meeting vendors will bring you gifts, etc use the NPC interaction for player choice ("What kind of weapon you need, traveler?" -> random player gift of weapon_type).(Note:This will be botted too, no overpowered gifts - the idea is to reduce dependence on treasure hunting and boss-farming).
E.Instanced treasure area, such as e.g. treasure cave. disconnected from in-world spawning.

Bosses:
1.If it drops items of any appreciable quality. Treat it as chest that will be camped by bots above.
2.Move important bosses to instanced dungeons. Don't let camping players farm some boss in open-world, it leaves a bad impression for lower-ranked players and breaks immersion. ONLY randomly generated bosses/bosspacks should ideally exist outside of instances.
3.Spawning location can't be confined. Always leave movement area.
4.Spawn outside of player view, i.e. preferred least active zone/area.

NPC:
1.Prespawn NPCs as soon as possible. Ideally they load after terrain. NPCs popping into view breaks immersion and is jarring.
2.Don't allow the NPCs to move much, their spawn point is static confined area.
3.Allow long-range interaction with NPC, since the spawn point will be filled with trading/questing/etc players and one-NPC bottleneck.
4.If possible, move important NPC interaction to UI elements:quests giving automatic to quest log when reaching area, trade to special "Vendor UI" that opens regardless of distance, Ideally NPC should just be talking about lore/quests without being required to find/click them(optional NPC).