That hamstrings the next few sets as well though, Wizards likes to be able to print Ulamogs and whatnot, and as long as you have Marvel in Standard they wouldn't be able to do that.
Yeah, that seems to me the most relevant drawback. I wonder if Nicky B. would have been worth trying to spin out of Marvel? Yes, I know he's been leaked, no I haven't looked at the leak and I don't want to.
Also getting to free-cast cards like
Baral's Expertise and various 'Walkers is still pretty good. Ulamog may have been one of the best targets, but he wasn't the only one.
Those cards are good, but they're not one-hit win conditions (
Chandra, Flamecaller comes fairly close I guess, but even that is worlds better than what Ugly does to you). You have the chance to interact and fight back against those. A turn-4 Ugly is gg 99% of the time. I just have a hard time believing that the Marvel deck would be impressive enough to warrant playing competitively without its 3 turn uber resilient win condition that sets the opponent back 2 turns on turn 4. And really it's a 2 turn win condition because unless you have a ridiculously aggressive deck a midrange shell like marvel's should have no problem stalling you out of your last remaining 8 or so cards (and that's assuming you can chump block one or both of those turns). WotC already said it's not statistically overly dominant, just not fun to play against when the opponent goes "oops, I win." Marvel just seems too random to be reliable unless you have a critical mass of cards you can hit that just basically win the game on the spot.
All that being said, banning Ulamog means they'd have banned 2 of the 3 eldrazi. Not a good place to be for the face cards of your sets.
As long as there are only one or maybe two pair bannings, I imagine it wouldn't be too difficult then your normal legality check. Oh, this deck has Marvel, does it have Ulamog? No? Ok. That said, it would be awful for judges at FNMs.
I think you're underestimating the resource hog deck checks are. They're not necessarily difficult, but they're tedious and adding one more angle to look out for is a compounding cognitive check that has to be made when looking at any deck. That kind of nook and cranny checking is both asking for someone to miss something and going to extend the length of time it takes to do a deck check.
The bans are getting ridiculous at this point. I feel like Wizards is trying to get around their bad development practices through this. A lot of people put the blame on the rapid availability of data, but things like
Felidar Guardian really make me question that assumption.
Also, people hate Combo... with a passion.
To be fair Cat Combo wasn't a "bad development practice" it was an honest mistake. A bad development practice is deliberately pushing a
new card subtype that can go in any deck. Yes, they have to promote their new toys, but they've been bitten by colorless/artifacts before. Both of these things are a part of what Play Design is purportedly being created to catch.