"Additionally, when I host Gladiator events, there are groups of people who just stand in one spot and spam single slashes, actually managing to win points."
I mean if you're New to this, this is exactly how Gms/Ets used to do the event i.e. allow any melee weps.
About removing the large sword: I mean not many would use the large sword therefore if players are annoyed they should kick the player(s) with large sword or simply use the vote gaining glitch to get a vote and get more votes on the same user if you already failed voting ( why - you would escape re-vote glitch(no one would find out if you do it once) and it's not fixed by the devs so mightaswell use it?)
If you don't like hosting this event, then make an event that is a duel with [glad] tag, although it's long but you'll get legit winners