What staples from MD-On (last format) are you referring to that didn't get replaced?
Azelf LA was supposed to get replaced by Rotom UD or Alph 4, Uxie LA was replaced by
Draw Supporters and Magnezone Prime, Bebe's Search was (sort of) replaced by Elm's Training Method and Pokemon Communication, Roseanne's Research got replaced by Pokemon Collector (sort of), yet Call Energy didn't get reprinted unfortunately and neither did Warp Point. What am I missing here?
Pokedrawer +, Pokedex Handy, Expert Belt, Broken Time Space, all of the SP engine, Luxury Ball, VS Seeker... Not to mention that the no one plays Rotom or Alph, but everyone played Azelf. Calling Magnezone a replacement for Uxie is like spitting on Uxie's grave; no one played Bebe's, but they were already playing Communication and Rosy's wasn't even legal last format. Calling those cards replacement for anything is borderline offensive IMO.
Oh that's right we have a counter to Donphan and Reshiram with Suicune/Entei LEGEND as proven by google Cawthorn's Deck at Worlds 2011, counters to Yanmega Prime with Magnezone Prime and Zekrom, counters to Zoroark with Donphan, there are answers to these cards but part of the problem is that they are either expensive to get ahold of or there isn't a cheap alternative that's just as good when our options in the current format are limited at the moment at least until Noble Victories is released in the next 2-3 months.
Have fun slipping a Entei Suicune Legend line into a deck as a counter, tell me how that goes. If you don't own a set of Yanmegas, you aren't going to do well in this format
Part of that problem is how the Black/White Rules have changed the metagame where most games are almost decided by a coin flip where If a player gets to go first the other player would have a disadvantage to catch up If they don't draw into a Collector in time.
And going second has format wasn't an advantage? There will always be an advantage to going a 1st or 2nd, it is generally how games work.
It's still very crucial these days for Trainer Lock decks running Vileplume or Gothitelle. Sure you can't Candy T1, so what? get 2 Oddish or 2 Gothita on the bench from a Collector and regardless If they Catcher one of them from the bench you will still get your Plume or Goth Lock by T2 granted you have a Candy in hand. It's still a solid counter against Catcher so it's not a bad play at all. People are running Typhlosion Prime over Emboar in Reshiram decks because of the threat of Emboar getting Catchered and having to waste 4 energies to retreat or get locked from playing Switch with Vileplume/Gothitelle. Suffice to say Catcher single-handedly killed ReshiBoar but not Reshiram itself.
It's funny, because Reshiboar was dead before Catcher came out >_>