It depends on the map. Mainly the size but also the layout and what’s happening there. I’d say:
- One next to each entrance – to make sure that when you enter the map you’ve got one, in case you die before reaching another one.
- One near to each location where players are likely to want to go in a hurry, like dungeons and world bosses.
- In towns, forts etc. Not necessarily all of them, but the bigger ones definitely. Partially just because it would give a fairly even distribution but also because it puts them close to merchants and other services and roads. Which makes it a logical starting point for activities in that area.
- Finally if there are any areas left which would take an unreasonably long time to get to (most likely because of the terrain) with that distribution and which aren’t made that way on purpose (like jumping puzzles) they could get a waypoint too.
But one waypoint can serve more than one of these purposes. For example Earthshake Waypoint is near the entrance to Fireheart Rise, the Elder’s Vale Pact camp and The Claw’s spawn point. Where possible they should be combined this way to avoid littering the map with them.
Depends on the map. Of those already existing, there doesn’t seem to be any with too much wp’s. Some maps could definitely use more (Southsun, Dry top), and some would be a lot better with more uncontestable wp’s (Orr is the best example, but NE corner of harathi, for example, can also get very bad if the event chain is up).