Not trying to backseat-mod for the GMs or anything, but I feel this needs to be said (and if it already has been said, I apologize).
You should be participating in GMtourneys to have fun. Many things can factor into "fun"; such as mod, hoster, friends, and so on, but prizes aren't a part of that. If you're looking for good items/tc prizes, you might as well do something else. I mean obviously, (speaking about myself when I was a Game Master), if you play a long lasting mod that requires skill, I would give you a half-way decent random prize. But if it was some luck-based, quick mod where there is little to no skill involved, you can expect to get a prize not so great.
I know this was a bit off topic, but it's something people tend to complain about in GMtourneys.
As for suggestions and my opinion.
1: I'd suggest laying off the "too random" mods. Mods where most of the people clearly don't know what to do or have ever played it before. Having mods people haven't played before isn't really a bad thing, but explain to them similarities of other mods it is like.
2: I don't know if this is a problem now, but it was a while ago when I was a GM. GMs; don't act like a smartass when hosting because you think you're entitled to respect. Don't go A-Wall when someone breaks a rule, Chill out and tell them to try not to do it again. Insta-muting/banning the guy and being a general dick in the room ruins the vibe in the tournament.
As for my opinion of the GMs, I think that they are good at what they do and they host fun things. Some people just need an attitude adjustment that would really make a difference when hosting.
I know this isn't really helpful in the sense of "spicing up" but I think these changes would indirectly do that, also by doing this, it would make rooms more enjoyable to be in.