Why Advance In Rank?

I don't understand the whole ranking system. Why on Earth would you want your brute to go back to level one? If you have a good destiny, is there any reason to choose to advance a rank after winning a tournament? I'd just pick the same destiny path, so why start over?

There seems to be less brutes the higher in rank you get too, so won't that actually make the game worse with less competition? I imagine it would get harder as well, since your opponents will have had the benefit of more destiny resets and will have more experience in choosing them.

The whole game be it v1 or muxxu is based on getting brutal legend.
And there's the answer to your questions.

and once you get BL, then you can start leveling.

what might still not clear to you is exploring your Destiny in a tree system in muxxu
in mybrute you get one single Destiny for your brute and you wont be able to change it.
but in muxxu you can change your Destiny after winning a Tournament and take a new Rank, or even keep your Destiny but take a new Rank just so you can try another path.
for example
at lvl 2 you get Feline Agility or Sai
if you pick Feline Agility you get a certain path A, but if you pick Sai you get a diffrent path B and so on.....

In fact you can almost always improve your destiny by trying different subpaths. If you don't understand that, you haven't understood the game at all.

And it's sooooo boring to level up endlessly.