There are a few cards that will most likely shift the metagame. And there are some that are playable but not going to be meta-shifting. Overall its a decent set, I like that there isnt 150 cards with 2/3rds of the rares being little promo things like in SV. Its a nice small set with some decently playable stuff and a few good cards.
You also have to rember this will be our BR set and we will already have to be re-forming our engines to makeup for some losses such as Claydol. We also will have a really huge meta-shifting set IMO in our CC set as we will probably get CATs and LL which both have really good cards.
Also don't forget that people were talking about stuff like this about Unleashed before nationals. It wasn't one of the greatest sets ever realesed but looking back on the Meta-Game of BRs, Nationals and looking foward towards Worlds I can say that a set that people complained about being a worthless filler set right before nationals really did shift the metagame a good bit. So Don't be so quick to count your sheep, or Pokemon in this case. Just let the meta decide on its own if Undaunted is a good set or not.