The thing you're missing out on here is that the ARENA is not meant to grind your skills in. It never was that way in Warband nor base M&B. It was always meant for you to just learn how to use your weapon, chambers, blocks, etc. It's not meant to grind skills in... so having a slider to give yourself more XP per engagement in an environment that has no limit is essentially tantamount to exploiting and cheating the game. In Warband it only gave you 5-10XP per engagement in the Arena and no one ever had an issue with that... why?
Because we ALL knew what it was meant for, learning the game and the weapons you use. Tournaments? Those can have high XP rewards, they're competitive. Battles? Absolutely need more XP reward and so do Sieges... but an Arena with literally Tier 1 scrubs the majority of the time? That's not a challenge and that's definitely not meant for grinding skills up to be a God or Lord of all. It just doesn't fit with the overall gameplay loop TW wants us to engage in... which is to venture the world, build a warband and conquer. That's how you become the better warrior and master your skill.
I'm afraid I'm now back to the position of "why do you care?" The solutions suggested mean that this change will make no difference to your campaign (genuinely this time). Why not just let other people play the game the way they want?
It's not really that different from having a slider to reduce the damage you take. Or playing on easy mode in other games. Mount and blade isn't Dark Souls, the selling point of the game isn't that it's the same for everyone and there's no difficulty setting. In fact, the selling point of the game is literally the opposite of that given that it's a sandbox. Just because you don't want to do it, doesn't mean others are the same.



