With Cats & Dogs, yes, I don't like sims to have cats or dogs if they can't take care of them properly and the pets don't have a large enough house or garden to run around in.
With the rodents from MFPS, I don't like them very much because they just bite my sims all the time, I only have one hamster in one save and I feed him and interact with him. I gave him a treat which makes so he doesn't die of old age but I never game him the treat which lowers his intelligence so that one day he might escape.
But he hasn't escaped yet, maybe he likes to stay where he is...
