Barrus is the bothersome NPC that stands and waits for your appropriate star certification, I believe any game that prevents you from progressing for the sake of "you're not ready" is bad. I feel Barrus should spar with you instead of checking to make sure you are prepared for the fight ahead, he a is a knight I am a knight training and sparring was prevalent with soldiers and knights alike.
What he should show you what you'd be up against by kicking your ass and if you successfully downed him he'd commemorate your bravery despite his efforts to convince you and the orb you receive at the end of the mission would also make more sense.
I don't want my countless progress to be halted because the game thinks I'm not ready, I want the game to show me I'm not ready instead of just telling me. As a challenge for myself I sold my armor, helmet, and sword and left myself with nothing but a 4* shield to see if I could build myself from the ground up and I've done several runs of arcade alone and with other players and have held my own despite the game thinking "I'm not ready" but just because I did this doesn't mean you should, I am making progress however.
However, as an act of laziness, I am just gonna get the ancient plate mail with set because I don't have to craft them because I'm lazy lol.
And the game can be very punishing if you aren't exceedingly careful and sparing. Without armor although I have a 4* sword and 4* shield it does make the game more difficult and as a person who hates himself I like difficulty in my videogames especially one of my favorite games "aesthetically" and as much as I love to play this game grinding to pass the hall of heroes is not one of my favorite things to do.
I think I can and have suffered without and have outright ignored the hall of heroes for extended periods of time only to return because if I want to get invested into this game's story I have to do the hall of heroes...
Despite all of what I've said I'm just a person who likes hard games, I'm glad this game has an elite mode, I'm glad this game has orbs of alchemy (for the most part), I'm glad this game is generous enough to suck money from me to let me revive, I'm glad this game is like the way it is (for the most part) I like this game and I want to continue liking it.
Again, however, this is all useless ramblings and most of which doesn't make sense from any point of view but my own and likely won't get any attention because of it.
You might find second half of this post interesting. Dates back to 2010: https://forums.spiralknights.com/en/node/775
I personally see this system as something that is meant to keep you in the game longer, give you goals, things to do, motivation.