For HK$110 per month, you can live like a king and queen, waited on hand and food every minute of the day!
Okay, maybe a slight exaggeration, but that is many times over the average family wage here. You would be able to get a very nice place to live in any but the most expensive and exclusive neighbourhoods in town for little more than $50k per month, including a live-in, permanent maid/nanny/housekeeper.
I can't comment on how easy it would be for your wife to find work, but I can tell you that under the current rules, if you have a sponsored employment visa, your wife does not need one - or to put it another way, she can get one just by asking, as your dependent. In effect, she would be included on your visa automatically. Not a problem.
Don't know about the pets, and you don't say where you're coming from, but a quick look at the appropriate government website says that you need to apply for a permit in advance, but:
Dogs and cats imported direct from U.K., Ireland, Australia, New Zealand, Fiji and Hawaii are normally exempted from quarantine, subject to full compliance with the permit conditions.
with a table listing most of the rest of the 'western' world.
Dogs and cats imported from the following 40 countries/places may be exempted from quarantine provided the animals comply fully with the permit conditions.
In other words, if your cats are healthy, have their shots - whatever's appropriate - and you can get a vet or two to certify that, it seems there's a good chance you'd be able to get them in without quarantine
Oh, and welcome to the site, and to Hong Kong. If you're getting paid that much, drinks are on you when you get here