Marth's style is spacing. Unlike Ike, Marth isn't Fair+.
That's Marth's DEFENSE. What do you think he does when he lands a combo starter? He juggles them with uair, fair, and sometimes nair. MOSTLY FAIR. Do you know why? Because fair's varying trajectories (tipping and not tipping) allows for the most control in the combo, letting Marth chose between sending the opponent up so he can follow up platforms for damage, or sending the opponent forward and down so he can finish the combo.
However, this is all done with Marth spending most of his time higher in the air. Sffl combos only work on fast fallers, against midweights his combos consist mostly of full hops and landing on platforms.
Believe it or not, Marth is not all about spacing pokes to land little bits of damage. Marth prefers NOT to reset the situation after a hit, he likes to stay on top of his opponent after his combo. He tries to end his combos in tech chases, edgeguards, or juggle traps, INSTEAD of just swatting them out again. Spacing is only what he uses to GET THE OPENING HIT, but once that's done he's supposed to be all over you and not let off.
SHFFLing a Fair is still just as good as it was before. You can tipper it, and the shieldstun allows for a free anything.
We're not talking about his approach. We've never been concerned about it as an approach. SHDF was a HORRIBLE approach and a BAD spacing tactic. But double aerials were useful IN COMBOS. Full hop double fair was certainly too safe on defense to be considered balanced, but it was also his main combo tactic and in that respect was far from broken (he's not the only character who whas combos like that <_<).
Considering he has more moves than Fair, I think he's fine. >.> Getting SHDF'd across the stage into Dair multiple times isn't fun, nor does he NEED it.
That combo really doesn't work for more than like 1 itteration. However, Short hop fair->uair->uptilt->ect was a pretty nice little combo. Or mixing it up with tipped fairs on the way down so that you could continue with fullhopped fairs next. Or a bunch of other little things that you could do like fair->double jump in order to land on platforms more quickly.
There are plenty of things that other characters have that they don't NEED. But the characters CAME WITH THEM and since they're not GAME BREAKING they're not being removed. The only "game breaking" (and really, it's matchup breaking, not game breaking) part of Marth's fair was it's safety out of a fullhop. No other defensive aspect of it was particularly broken, nor was ANY offensive aspect of it broken.
Good yes, but not good enough to be taken away.
Try SideB to Fair. Works just as good. And guess what? It's actually FASTER than SHDF.
Side B does not combo into fair. Side B ONLY combos into side B, and is otherwise unsafe on hit. Looks like someone who doesn't play Marth is telling us what Marth is supposed to be <_<