...Marth's setup's don't work past like 70, so I dunno what you're talking about, lol. You're not going to FThrow tipper someone at 100%. And do you legitimately believe that ken combo is what makes Marth a good character, or am I missing something?
If you seriously think that all Marth has are Fthrow tippers and Ken combo then it's not wonder you think so poorly of Marth. Marth has one of, if not THE best grab game. Uthrow leads to juggles which wrack up serious damage, Fthrow leads to tech chases and so does Dthrow, and Bthrow leads to bair.
Fthrow tech chase Fsmash works at an %, Bthrow tech chase Fsmash works at an %, and it's not that hard to do with the proper read. If you've been playing Marth for a long time, you'd know the exact distance you need to stand to get a tipper, in fact, it was one of the first things I learned as a Marth main. Floaties don't get tech chased by Fthrow/Bthrow since they can act out before they hit the ground at about 70% (depends on DI, they have to DI up iirc) but Bthrow pivot Fsmash is a DI mix up which you can get tippers off of on any unsuspecting opponents.
Ftilt, Utilt, and Dtilt in neutral can stuff almost any approach your opponent tries.
Marth is also the king of juggling. He destroys fast fallers all the way down to about Roy's weight with SHFFL Uair juggles. There is no way Roy can get down once Marth starts to juggle unless the Marth messes up, or Roy does a well timed counter (which is risky in of itself).
tl;dr
Marth has more to his game then Fthrow Fsmash, and ken combo. A short read through the Marth discussions will show you just how much killing potential this character has.
Why does everyone say that PM is so floaty? Regular falling speeds off of shorthops and while comboing are actually pretty much insignificantly different when you take averages across the board. Lots of good fastfallers in this game; Wolf is the same falling speed as Falco, and Lucas falls as fast as Falcon. Terminal velocities are actually faster in PM than Melee's S and A tier, but there's only a difference of about .01 units and that's pretty much irrelevant anyway.
Actually, Wolf is slightly heavier than Falco, but it's not that big of a difference so yeah. Just so you know, not trying to nitpick.