@The:
I liked smoker because he was a cool guy and the first named Marine that wasn't a dick to everyone, however I don't really recall much onscreen achievements. Dragon cockblocked him at Lougetown, and he called back-up during the Alabasta arc, but that's about it. He fought Hancock, but that wasn't an onscreen fight. I do want to see Smoker do something that becomes worth-it, but it may be more of a fighting corruption and less taking on enemies.
But, as you can recall, he took care of Luffy effortlessly at Lougetown, and Luffy had to be safed.
He saved their asses during Alabasta, with him knowing perfectly which croc ate the key. He also faced and tied with Ace.
And then, lest we forget, it was heavily implied that it was he who brought the rain that ended Alabasta civil war.
And even at Marineford, he did pinned Luffy down. It was all quite impressive.
And the PH happened.
@The:
As far as curbstomping from an Admiral, I don't expect that to happen exactly, at least not a number of named characters being taken down effortlessly. Yes an Admiral shouldn't have to go all out against everyone either. I guess we just have very different expectations. Also, the way I see it, You are going to have to wait a long time for any type of payoff. If we go by how the pre-time skip stuff, Ace and the fact that the Whitebeard crew existed got introduced beginning of Alabasta. It wasn't till 300+ chapters later that anything came out of that. That was also the time Marines actually had a huge role. So you're in the long haul for anything with Marines. Hopefully you are invested in other things besides the Marines if that's the case.
Do you recall an introduction to Akainu?
And do you also recall that there were all New World Pirates at that battle?
And I don't even want that. I want him to feel as threatning at the other three did. And he doesn't. At all.
More to the point, yes, I am invested in other things besides the marines. Problems:
A) Other things are not good or entertaining enough for me to distract from the marines. At the moment, anyway.
B) All those things you mentioned? Characters are shown for a chapter or two, three at max, and the leave for their own adventures. It feels natural and is a rather good setup.
Fujitora doesn't leave. He is an integral part of the arc. WHY? What does him being there accomplish?!
C) The final one: If you don't plan on them being anything but setup, DO NOT MAKE THEM INTEGRAL PART OF THE ARC!