To make the Gladiator Games even remotely interesting for any player who is not amongst the top 100 of the server I suggest two changes:
1. Introduce Categories. Four or perhaps even six different categories to compete in.
2. The defensive power of the troops entered into Gladiator Games on first entry is final and cannot be changed till the end of the games. (Even if new items are picked up or new skills/troop improvements are unlocked in the week the games are running.)
The defensive power will determine the category in which a player competes for the entire period the games are running.
The advantage of having those categories is that smaller players have as much motivation to compete as the top guys, seeing they might have a chance to win their category.
Fixing the defensive strength for the entire duration will prevent strong players from entering weak troops to be classified lower whilst using powerful troops to compete.