This part of the list is a bit less important, and everything after is even less significant. But here is my rendition of B-tiers (11-20) with as much explanation as I can. I won't go further, but these are characters that are held back by 1 or 2 issues.
11.
See above.
"Mario can rack up %, but he struggles (more than the top-tiers) to actually secure a kill."
12. Palutena is the DI queen. If you don't know how to DI properly when facing her, you will
definitely lose. D-throw can vortex until ~60%, and at higher %'s it can true combo into U-smash for a godlike setup.
haha Her weakness is that she lacks a strong combo breaker, and can be combo fodder for a lot of the top-tiers. Still, she is a huge threat.
13.
Ness can definitely kill, but he lacks a solid approach option. Side-B has a lot of potential to set up, but it is easily spotted and punished. Even with less lag on aerials, his F-air and B-air are NOT safe in neutral. Ness needs a huge read to break the neutral, but with one, he can tear an opponent down with relative ease.
14.
Peach is a very grounded fighter, she loves to put the opponent above her and react. Turnips have more tact now that HG limits overall movement capabilities. D-throw combos into F-tilt at low %'s, which can then be followed by a B-air, N-air, or even F-air if you're quick enough. Very defensive, but at the same time she is very hard to breach. (She can float cancel too)
15.
Toon Link is one of the only characters that can cover the whole stage with hitboxes at the same time. His aerials are extremely safe (especially N-air, which can trip). Boomerang can even combo into F-air as well as bombs, but landing a projectile on a quick opponent can be difficult. Has some amazing match-ups, but pretty horrible ones at the same time.
16.
Mewtwo is interesting to me, because he is now riskier than ever. He is easily combo'd, and his neutral game is par at best. However, Mewtwo is right behind Marth in 0-Death capability, all it takes is a grab. U-tilt or D-tilt can set up for a FF N-air, which can lead to another grab. His N-air is the best off-stage move period, especially if you rise it to deny someone the ledge. (also N-air can spike fast-fallers btw, its disgusting...)
17.
I absolutely love Falco (he's my main), but he has some glaring flaws in SLHG that hold him back in the tiers. This boy has more setups than anyone I'm pretty sure.
D-throw > D-air > U-tilt > U-smash > B-air, D-tilt > D-air (off-stage), U-throw > D-air, and U-throw > U-air > D-air. His flaw is his capability to
drop setups. If an opponent wiggles out of his combos at high %'s, Falco
really struggles to finish his opponent off...
18.
Doc has some the best offensive neutral tools in the game (better than Mario). Once he gets his hands on you, be prepared to eat a long and impressive combo with lots of pain. The only way to beat a Doc is to simply outplay him in neutral, then capitalize on his weak defensive tools. Doc has a lot more going for him offensively when compared to Mario, but a lot less defensively too. (ie. Risky)
19.
Villager can freely zone and punish, without fear of being zoned himself. His off-stage game is superb, all it takes is a F-air or N-air off-stage to take a stock. Unfortunately, he requires quite a bit of setup and prediction to be optimized, and that can become increasingly difficult against Sheik, Fox, Mario etc.
20.
Greninja has unlimited potential, but his difficulty of play is the only thing holding him back. His movements need to be tight, his aerials need to be placed correctly, and he needs to be mentally composed in order to maintain pressure. He can lose his combo very easily with a wrong input, but if done with extreme precision, he can 0-death in the flashiest way possible.
Here's a visual, again this is all my impression after a lot of games. http://i.imgur.com/vcfujNs.jpg