All champions are good. A good Master Yi will get out of bronze as easily as a good Twisted Fate or Akali. If you're looking to get good at the game you need to learn macro and pick a few champions to learn the micro of. Pick champions you enjoy.
If you just want to "cheese" your way out of Bronze pick Annie or Garen or Tryndamere. Master Yi is a good choice from the jungle, but if you just wanna cheese it solo lanes are probably the way to go...
jungler -> Vi or udyr
top -> garen or jax
or actually just pick pantheon for every where, that ridiculous shield and poke is hated by everyone else.
Even veigar is a good option, drag the game and press R to win.
go [Xin Zhao] or [Vi] if u are a jungler. These 2 have good early and mid game control, healthy jungle clear, and are really good at 1v1s and gankings.
If you just want to "cheese" your way out of Bronze pick
top -> garen or jax
or actually just pick pantheon for every where, that ridiculous shield and poke is hated by everyone else.
Even veigar is a good option, drag the game and press R to win.
If not, go a powerful offensive jungler.