The big thing was that it was just dumb as hell of them not to dodge the on-coming Scandal train. The second ABC pushed that premiere back a week, the network should've been like "Yeeeah, let's not." They're both soapy shows, I can't fathom how they wouldn't think that show's return-- after almost a year off the air-- would eat into the show's viewership any. Riverdale's premiere going up against Scandal week 2 would've been more or less okay (even if I do question the timeslot), but both premieres going head to head? Come on...
That's the main one, but the show's promo game was also off. Title aside-- and outside of comic devotees, I don't know whether the town's name would ring bells for the general audience-- there was little to tell the world this was based off a comic that's been around for 75 straight years. The show's creative team is a guy behind literally all the network's top-rated shows AND someone that wrote for Supergirl last season, and there was no mention of either of them on posters/promos OR those other shows. Instead they used "From the network that brought you Gossip Girl (a show that ended almost five years ago) and The Vampire Diaries (a show heading into it's final hours)"... The pilot was the most buzzed about of the crop they picked up back in May, I don't even get why it wasn't on in the fall. I mean, if the network really wanted this thing to be big, they had a bizarre way of going about it.
The good/decent news is that The CW's views on ratings are different than other networks. They take into account a lot of factors, whereas others tend to make decisions based on live numbers alone. There's online/social media engagement, which I saw a lot of last night, it was trending right up there with the TGIT shows. There's critical praise, which they're in no position to turn their nose up at, and the show is, what? High 80s on RottenTomatoes? And then there's delayed viewing, which-- if I'm right about Scandal eating into the show's potential audience-- could end up being substantial on DVR/on demand/streaming. Even the live numbers are at around the same level as the other newbies this season, not below. And when you consider that at least one of those shows had a much more impressive lead-in in The Flash, I think things are... okay. Some steadiness in live numbers certainly wouldn't hurt, though.