You are pretty much right. Just look at how there are only three new popularly requested characters (Palutena, Shulk, Chrom) compared the kind of new characters that popped up between Melee and Brawl.
Most of the most wanted newcomers for Smash 4 are retreads from pre-Brawl, and two of the Top 5 are even Melee veterans. Throwing out the Melee veterans, you are only left with three characters that there appears to be a passion for that mirrors what we saw with pre-Brawl, Ridley, K. Rool, and Little Mac (and maaaybe Paltuena).
I mean I don't think there would be anger if Bowser Jr., Paper Mario, Dixie Kong, Isaac, Shulk, Chrom, Toad, Krystal, or Waluigi didn't make it in Smash 4.
The only three newcomers this time I can actually see people being upset with their exclusion would be the three mentioned above (Ridley, K. Rool, Little Mac, and a maybe to Palutena).