Net Cull Distance (NCD) is a good starting point. Think of it as a sphere around your character that helps determine relevancy. Anything inside is relevant (considered for replication), nothing outside is considered, unless “Always Relevant” is set to true on the specific actor.
Characters should have the highest priority and their NCD should be set to account for the distance needed.
For example if you want characters that are 100m away to be considered, then NCD should be set for a minimum of 100m.
How far out is a game design choice. Small map arena games use smaller values. Large open worlds with long sight lines use higher values.
e.g.
Player Unknowns Battle Grounds (PuBG) has a 960 to 980m NCD and a render cull that’s pretty close to that.
You definitely want to dial in your values here. Don’t just throw in a huge number and be done with it. There’s a performance cost attached.
Debugging will be a bit easier once you have your NCD dialed in.