I have an idea for the replay system. Add a save function that will save a specific replay, and if a replay has been saved, it can be looked at by the moderators.
This could be helpful as for example someone hacks and a player other than the hacker used the replay function to save the replay, then the player who wants to report this hacker can ask a moderator to look at a specified saved replay to determine wether or not the reported player hacked.
This is just an idea and if done right it could help to get rid off those hackers that didnt got caught by the anticheat.
That can be possible. Recently, Hypixel added a anti-cheat system that works almost exactly like your idea. Someone reports a hacker, and the community looks at the re-play and decides if they are hacking or not. I do hope The Hive adds this.
but hopefully they will