Okay: the new Thing is way lame, and his powers are, while authentic, boring. The new Invisible Woman sculpt is also lame, certainly not as good as the last one, and her powers are incredibly worse (at least at Rookie level, probably at Experienced as well). The new Human Torch is cool, and I'm willing to bet that the REV will be quite similar--all of the other FF members have LE sculpts that perfectly match the REVs so Torch might be the same. The new Mr. Fantastic model is arguably better than the old one, but his powers and point cost are unequivocally improved--especially in combo with Brilliant Tactician, which I'm going to say is the best feat in the set.
And that's in a set with some dang cool feats: Unstoppable, Shake Off, and Thunderbolts are all amazing. But Brilliant Tactician sill be very hard to beat--imagine it on an X-Men team or a Batman Enemy team where you could really abuse it. Me likey. I also like the implication in the Shake Off card art that there will be a giant-sized Hulk.
As for the other characters...I'm not sold yet. At this point I'm still in "buy the FF and a set of feats on ebay" territory. They'll need some killer figures to entice me to buy any boosters, let alone a significant number of them.