What I love about Bannerlord, and Mount & Blade in general, is that the moment you are plopped into Calradia you can do absolutely anything you want (within the limits of the game mechanics, of course). I think the game needs more sub-features or quests to incentivize the tournament gladiator and mercenary playstyle to be able to live off of these lifestyles. Things like meeting NPCs that you can only find through tournaments, and then be able to earn more renown and maybe extra money if the player lands the finishing blow to those NPCs in a fight would be cool (for balance, extra player renown is offset by NPC renown, ex: the higher their renown, the higher you earn in odds). As for living the whole game as a mercenary, as long as the player is not part of a kingdom, they can buy land or homes in other kingdoms where they can put captured slaves to work or have a place to drop off excess troops at. Maybe this is too much and would best be done as a mod.