I like guarding the dump. I find it rewarding.
I have 4 positions I can start in: safe, face, tiger and sumo. By position, I mean where I stand on the field relative to the dump.
Let's consider these positions for the situation where the thrower is on the line, forced line. The dump is 5 metres away, level with the thrower (ie not upfield or downfield but in between).
This is where most people stand. Generally denies upfield cuts. Allows the thrower to turn and dump immediately, with little cutting required by the dump. Most dumps are used to being marked this way.
This involves facemarking the dump, and standing between them and the disc. The dump is equally open if they cut left or right. But they usually have to spend several seconds cutting to get free.
For this position, stand downfield of the dump. This takes away the easy backwards pass. The up-the-line cut is more vulnerable. But if you know where the dump will cut and have a speed advantage, this is not a big problem. Additionally, if the dump cuts up the line and doesn't get the disc, the thrower has no dump anymore. This is an aggressive tactic, so I call it tiger.
Same as safe, except closer. Real close. If a player is successfully cutting up the line, stand close, with your feet apart. The dump will have to make more of a cut around you to go up the line. In a safe stance, you are usually side-on and moving when they get close to you. Sumo changes this. I call this sumo, as you are trying to look big.
You can work out how these positions would apply in different situations, e.g. if the force was a force middle. Or the thrower was left handed. Or the disc was in the middle of the field. Or a teammate was helping you by poaching in front of the thrower.
I think I might need to change the names - safe and face sound too similar. And I don't know if tiger aptly describes that position.
Lastly, remember that everyone likes to throw backhand dumps. If you want to allow a throwing option, make it a forehand.