Here's a temporary solution: borrow a temporary anticheat such as Spigot's AAC.
If not that or if it takes too long, then the sarcastic (and simple!) solution: CubeCraft will allow hacking.
Bottom line is people are demanding for a fix asap (even a temporary fix will do!) to either the punishment system or the anticheat. Us players understand that an anticheat takes a long time to code, but the least we want is a more strict system. People WILL leave quickly just like they did when Mineplex had its hacker problem. Last year Mineplex was at 20-30k; now it's 10k (at least half of what it used to have, 10k behind Hypixel) and sometimes has fewer people than Cube has at certain times of the day. The rate it's going Cube WILL suffer the same fate and lose players (possibly go down to as many players as HiveMC does currently). That will lower the server's revenue, the server's chances of competing against other servers, and amount of people willing to donate.