Two questions

So far I LOVE the game

Two questions tho

1. How do the DLC dungeons change the gameplay experience? Im still fairly early, I just had the scene where they show the logo of the game (despite playing 10 hours already lol).

Im interested in the farming dungeons but I worry that buying them now would ruin the intended game balance and I would get bored from not being challenged by the game. Is it better to save it for the end game?

2. I really like Wizardmon. But he is only Champion stage. However, if my understanding of the game mechanics is correct I can basically evolve him into higher levels, get higher stats, then devolve and have the blue stats make him as strong as higher stages even if he stays as a Champion. Is this correct?