1. As per the recent Delhi high court ruling the mother-in-law can seek a protection against daughter -in-law under protection of women from domestic violence act 2005, so I strongly advise you to use this option if the house is not in your and your wife' names.
2. Regarding the apprehension of criminal actions Under IPC 498A, you should not worry as the supreme court has come down heavily on the misuse of 498A and specified guidelines. getting anticipatory bail or bail is not any troublesome affair as there is always an apprehension that a wife come up with 498A as a weapon to fight against the divorce filed by the husband on cruelty grounds.
3. Your wife can get maintenance as she is not earning, saving this there is no hurdles to obtain a divorce under the given circumstances.
4. You should initiate legal steps to file for divorce, engage an advocate and discuss the best way to proceed considering your job and family's convenience.
5. once you send a legal notice or summons from the court , or even tll them that you have already filed petition , they will stop their pressure tactics and advise your wife to take the help of an advocate.
6. She can stay in your house unless there is a refraining order from the court, till her appeal and final order in divorce.
7. Do you have kids, how many years since you are married? you will get a chance in the court for mediation and settlement once the divorce proceedings starts,then you see whether there is a chance of mutual consent divorce and finish the matter .
8. Your mother can get a restraining order under civil law as well as criminal law, also will be considered her status as a senior citizen, such a situation, you can agree to offer for a rental accommodation to your wife till the final order of the divorce.
9. In case of a FIR under 498A, your sisters can get bail and obtain exemption from appearance as they are working and living with their respective family in abroad.There is less chance the police include them and file FIR against them.