Compared to all of our other (Java) gamemodes, TIMV was a complicated game with a lot of nuance, and a steep learning curve, and for newer players, it was often difficult to fully understand the game and its rules. This led to a lot of players - knowingly or unknowingly - breaking the rules by killing players randomly (we called this ‘random deathmatch’, or RDM).
The high amount of disruption caused by RDM (among other things) meant that TIMV took up a very disproportionate amount of staff time, both on the part of the moderators who had to spend countless hours enforcing the rules (when they could have been looking into more disruptive things, like cheating), and on the part of our developers, who had to spend a lot of time coming up with and implementing game mechanics to help to prevent it.
At its core, Murder Mystery is similar to TIMV in a lot of ways, but is lot easier to understand for newer players, and can’t be completely derailed by a few users randomly killing everyone in each game!