Josh, caring for animals is very expensive, an admirable project you want to do, there are, like you said a lot of costs involved and on going costs for those animals like vets bills as some animals you want to care for might have underlying problems just like us humans ie: epilepsy and diabetes etc, treatment for those alone will cost a lot of money. If you decide to make it a charity, there are still the "will we meet our target amount per month to cater for the animals needs" running through your mind. If those targets aren't met, the finacial costs will have to come out of your pocket.
Taking on a few animals and working part time might work out for you so you can get the feel of it and your wife can help out..(no extra staff required for the time being)
As for the job, there will be many here who would envy you just having a job. But besides that when you are starting something up in the form of a business a lot of it will be from your own pocket and this could go on for at least a year, all of your luxuries will have to go on the back burner like holidays for example.
There is a question you should ask yourself though......Do you work to live or live to work?
