Alright. I'm trying to understand the argument of "Much more reward for the risk"

You get a weapon and can't change it out yes. But winning the Event gets you.

Quickness (the best 'ability' out there)
and 4 Stars of Experience (if they started with none) and a good percentage of the time a place in the HoF (if they were not in it already) so a HoF ability.

That is +4 Att, +4 Def, +4 Prec ...

I don't know if I want an event that has a reward so good that if I don't throw my pretender at it, that I have drastically weakened my position. As it is, the winner can pick an already decent supercombatant and put him in the Arena and have him come out even better and potentially much harder to kill.

If he had Sacred, or Always Blessed (like a Prophet) even better, but I don't think a big pile of gems or gold would be an answer for it.