Probably dog person since I've had more interaction and taking care of them in my life I guess. I don't mind cats but tbh those I've been around that is not randoms you see on the street hasn't really been trained and taken care of properly so.
this isn't my westie but i'm getting one soon i've took care of dogs before and particularly with westies i have a connection. i seem to get along great with dogs, but not cats. don't know why, but i prefer dogs anyway so no matter.
When I absolutely have to choose one, I go with dogs just because I've always liked underdogs (haha) and dogs tend to be less popular, but I really adore both!!
As for dog and cat villagers I have, I have Felicity and Marcel in Lunavila, Kiki in Drowsy, and Lucky in Solavila. I have another town idea that I plan on starting in the future, that I might get Bob, Cookie, and/or Katt for.
My two dog dreamies are Biskit and Portia (I currently have Biskit, but Portia left a few months ago ). I also want Cherry and Mac, but as I've never had them before and don't know for sure if I'll like them, I don't consider them dreamies yet.
I love both but I generally prefer cats, even though they can be little jerks like my cat walking across my keyboard a few seconds ago. I don't have any cat/dog dreamies currently but I used to want Shep and Kabuki.