Exactly, there’s different variants, for example, I avoided this kind of grind and I just went directly to random BGs for Honor and 2s, 3s with my healer, now I do more Solo Shuffle compared to other options, there’s options compared to the issue with a rare that spawns every 1-3 hours.
Obviously if you focus so much in the war crates, you’ll find issues like faction imbalance, random locations as you mentioned.
That’s the case of your specific grind, as you mentioned rare will become easier regarding competition but that doesn’t remove the fact that the respawn will be the same, also it’ll be harder for some cases because as mentioned by another council post:
Exploit early, exploit often…for example the mount from Zaralek Caverns Seething Slug, reward from the cache that you need to click some orbs.
Fix: Seething Cache now correctly cancels Insidious Insight on all players after being looted by the first player to reach it
I did it when picking the cache didn’t remove that buff and that specific fix wasn’t receive well. Also, as you mentioned before some content is easier to do it when it’s new do it realm hop and other strategies.