Do you not think Snake carrying that ridiculous supply of grenades and c4 adds a few pounds? Either way, it's a kinda silly point. If I were designing the game from the ground up, Snake would not be heavier than King Dedede and Charizard (neither would Ganondorf). However, I'm not designing the game from the ground up, and changing it probably has more downsides than upsides.
I kinda don't want to get carried away with a long post again since I've mostly said how I see things, but there are important points I think some people are missing.
Peach's fthrow is a "back up" kill move, not a real one. I don't understand why it should be a real kill move; killing throws are a special thing in Brawl Peach definitely does not deserve (in standard Brawl, Ness and Olimar are the only two with really good ones while Squirtle, Charizard, and Lucas have decent ones). I definitely couldn't care less how powerful Peach's fthrow was in Melee, just in case anyone wants to consider that.
The way Peach's fthrow is optimally used for killing is similar to how Samus should be using dash attack or R.O.B. should be using uthrow. You don't actually want to use these moves for killing moves. Rather, they're much easier to land than your "real" kill moves, and if the opponent stalls you out and forces you to merely rack damage for too long, they eventually seal the deal. The buff has this role in mind. It does not actually add a real kill move to Peach's arsenal (it would be a ridiculous addition that would obsolete all of her other kill options since grab -> fthrow is far and away easier to land than her current kill moves). It rather just lowers the damage to which an opponent who is successfully avoiding Peach's real kill moves can expect to survive. Your main goal with Peach should be to land those other kill moves at earlier percentages. The fthrow is just there to make it less horrible for the situations in which you can't.
Ness is so misunderstood. Fsmash this fsmash that like it's a core Ness move? Pk Fire as one of Ness's primary moves for that matter? Ness's most important five moves are his five aerials; all of them are good (fair in particular is just super good). His next most important move is Pk Thunder. I'm not sure how you classify it in terms of moves, but Ness relies on his grab game more than anything else for grounded combat.
Let's just look at Ness's aerials, honestly. Nair has surprisingly decent hitboxes (don't be fooled by the uninspiring animation) and is all around really fast. Anyone who has ever played an actually good Ness should know what I'm talking about; Ness jumps back from the ledge with nair and he's legitimately hard to stop just because of how fast he gets the hit out and the hit is actually not low range/priority like you'd expect it to be (rather it's more like medium). Ness's bair hits very hard with both high damage and kill power, and it's decently quick even. The hitboxes (including the sweetspot!) extend through Ness's body; you don't need precise spacing to land this at all (rather, you just need to be vaguely near to land it). Uair is like the best of both those words for fighting opponents above. It's a great kill move, does good damage, has surprisingly good priority, is fast in terms of start-up, cooldown, and landing lag, and is really just flat out easy to land.
Ness's fair is a ridiculous move that comes out faster than most aerials and simultaneously has that crazy non-constant range and transcendent priority. If Ness does retreating fair, I think literally the only character in the game who can outrange him with another aerial is Ike. I know he outranges G&W's turtle with that (which is G&W's longest range aerial). Note that Ness's air control is really good (specifically his acceleration which is what he needs to be unpredictable like this; his top speed is merely average) so he could make a neutral or advancing fair into a retreating one unexpectedly; the way fair works (and dash attack for that matter) is that it generates hitboxes that are the sparkles and they linger in one place for a while independent of where Ness moves. He generates a series of them, and if he moves in different ways while he does it they form different patterns and sometimes leave hitboxes very far from Ness. Fair is even pretty good if he does raw neutral jump it or advance it; it's still a fast, disjointed, transcendent attack.
Ness's dair is also an amazing move. Ness has above average mobility when he's jumping (and if you are Ness, why are you not jumping?). Ness's dair has much of the same advantage on hit as Ganondorf's. It is a ridiculous combo move when it hits a grounded opponent, it's a safe move, and off-stage it kills at around 30% as a meteor (highest base knockback out of any meteor in the game). Maybe you have to play an actually good Ness to appreciate this move, but it's just really, really good. It's really not that hard to land and especially not risky to attempt to land, and the advantages for landing it are really big. It is just a very skewed in Ness's favor move in terms of risk-reward.
For that matter, look at the general theme with his aerials. They're all fast. They're all safe. They all have at least decent hitboxes. When Ness is jumping around, Ness can use his aerials with impunity. This is exactly what Jigglypuff and Meta Knight do. Feel free to use aerial attacks with a liberal abandon because, if you end up getting hit, it will be because of bad positioning or something, not because your aerial was punished because your aerials aren't punishable. I remember laughing a bit to myself when talking to a friend of mine who mains Ness after seeing him make a few elementary mistakes playing as Marth. His excuse was that he wasn't used to having to be careful about using his aerials at appropriate times. This is the main good thing about Ness, and the nature of the constant commentary about him suggests a lack of understanding of this.
Pk Fire is a trickshot move. It's hard to land and not very safe to throw out. It sets up for stuff great on hit. You use it seldom and as a surprise mostly. Ness should not be relying on Pk Fire as a core of his strategy so much as, well, a trickshot. I don't see why we'd want to change Ness to make him reliant on it as such.
Fsmash has several uses and is not as horrible of a move as people think, but it's not really a core of Ness's game. In fact, it's a move to dissuade as much as anything. If Ness predicts his opponent doing something punishable (such as suffering lengthy landing lag from an aerial, something that Ness himself doesn't worry about!), Ness fsmashes it. Ness's fsmash hits really hard. It's like you failed to hit Ness with your one hit and he hit you with the power equivalent of three hits. Most people will just stop doing those things that let Ness land the fsmashes, and Ness will stop using fsmash. That's fine. Fsmash did its job. Now the opponent is using a more limited set of options. The point of Milk's video was largely showing off clever uses of the reflecting properties of fsmash too; I only would have to be killed by a reflected laser as R.O.B. once or twice before I'd have a little more respect for the move.
Making fsmash faster would totally change the nature of the move. Ness doesn't need it as a fast general purpose grounded attack. If he had a tool like that, it would completely change his nature as a character. If Ness wants to hit you with a fast KO move on the ground, he should use his ridiculous dash grab to land a bthrow.
This is far from a complete summary of all the good stuff Ness can do, but it's the real heart and soul of his game. I get a sense so much Ness commentary comes from perspectives that have never even played against a decent Ness; it's frustrating. It would be like reading Jigglypuff discussion about the need to buff her dtilt...
