Thank you for your question
My name is Clare
I shall do my best to help you but I need some further informtaion first.
For clarity what is your net income?
Do you take that as earnings or dividends?
And do you pay Income Tax on that?
So what is your income AFTER tax and National Insurance each year?
Then you have no problem - you already earn sufficient and if your wife can pass the English test then there is no reason why her applictaion will not succeed.
Please ask if you need further details