When you compare pokemon to previous pokemon "by generation", your comparison is not justified if you pick Vanillite and Klink and compare them to Eevee, Gyarados and Arcanine... yeah no.
Yeah, yeah, HURR DURR GEN 1 IS JUZT AS WERD LUK AT TANGLA AND PORGON AND HITCHAN AND COUGHING AND YEEEEEEEEEEEEEEHHHHH!!!!11111
Ahem, although these Pokemon are odd, they all have a nice air of simplicity to them. That simplicity is what used to define a Pokemon. And before you whine about Koffing and Weezing's skull-and-crossbones symbols, they are there for a good reason: to indicate toxicity.
Either way, Vanillite is based off of ice cream. Stop trying to deny it.
Old Pokemon were all about having an origin, whether it be an animal or an odd creative spark. New Pokemon are all about shoving as much crap on the screen as possible. You got multicolored spikes, bright patterns, and pointless armor.
And if you think that there is no difference between old and new Pokemon, then look at this: