At this point my guess is by April or May application will be processed so is it good idea to apply for visitor visa for spouse?
Will it cause delay in PR application ?
If there is no impact on PR application, I might give it a try.
You can try that many have success but refusal rate is higher when souse is already sponsored to come here. If U R A Citizen here why not go visit souse for 2-3 months which will be a +ve for the file as well. On the other side there is no -VE if apply for her to visit you.
Also few things if U apply for a visit Visa, even for a spouse; one of the most important requirements for a Temporary Resident Visa is to show that your stay is in fact temporary in Canada. The officer at the port of entry must be satisfied with your intent to leave Canada at the end of your visit. One of the ways you can demonstrate that your stay is temporary is by providing proof of the fact that you have something or someone to go back to. Your ties to your home country can be displayed in many ways.
For example:- you have family to go back to or a job that you will be resuming up on return. But what if you don’t have either? There are many small but relevant things that are part of our lives that tie us to our home country. Do you own a home or a lease? If yes, then your lease or mortgage agreements can display your ties to your home country. Financial assets such as, bank accounts, stocks and bonds, can help you demonstrate your intent to go back. In order to make a strong application it is important to provide a combination of these documents.
AND don't forget spouse may need to show a Return Ticket, means two way, double the amount usually.