The ease of getting a Canadian visa depends solely on your nationality, residency, and financial means. I've had wealthy relatives and friends from India and Afghanistan who have applied for a Canadian visitor visa and been denied because, even with crazy high incomes, the Canadian visa officers were not satisfied that the person will return home after their trip.
You will need to prove financial stability for any visa application. This doesn't necessarily need to be in your wife's name - if you have an income and can provide proof (bank statements, payslips, letter from employer), that would be sufficient.
If your wife is legally resident in the UK and you are applying from the UK, this will greatly improve her chances. Ultimately a visa national who is legally resident of an OECD country (like UK) is viewed as less of risk for overstaying, and they're more likely to be granted a visa.