How much time can my Mexican wife and my son stay with me in the UK while working my 6 months before Family/Spouse visa application? [closed]

I hope someone can help.

I have read a bunch of posts about family visas, but can't find reference my questions, so I hope someone can give some insight.

Some background first.

I am a British Citizen. my wife is Mexican and we have a 2-year-old son, who is also British.

My wife and I have been in a relationship for over 11 years and got married in 2016.

During the 11 years of our relationship, we have visited the UK almost every year to visit family, Christmas etc. and have always left the country on time.

My wife still has her parents and a large family still in Mexico.

We have recently been living and working in Chile until last year when I lost my job.

In December 2018, we decided to move back to the UK as my parents are old and unwell and I have a better chance of finding a decent job.

We all traveled to the UK, myself, my wife, my son, my dog. Of course, I know better now, but at the time, I foolishly thought that my wife staying with me in England was a simple process. Now we have done the research, we realize it is a little more complicated than we imagined.

Fortunately, when we arrived at the UK border in a van full of cases and a dog cage, the border agent stamped my wife's passport for 6 months.

My wife and son are returning to Mexico after being with me for 4 months, as she obviously needs to leave before her 6-month passport stamp expires.

I am currently looking for work in the hope that I can get a decent job, and after 6 months, apply for a Family/spouse Visa so that my wife and son can finally be in England with me.

So finally to my questions... sorry for the long intro.

While I am working the 6 months period, is it ok for my wife and son to come to England to visit? I really don't like the idea of not seeing them for 6 months.

If they can come and visit, is it recommended not to return until after 4 months? (the time they have just spent in the UK),

After that time, would it be ok for them to come for 2 months and then return to Mexico for 2 months, then visit again? What do you feel are the correct limits to this?

I have read that if a customs/border agent feels that someone is trying to live in the UK without a visa, they can be rejected entry. Obviously, I want to be with my wife and son as much as possible, but I don't want to damage our chances of getting a long term visa. We really want to do the process properly.

Would the border agents see it as a bad thing that a wife and child are coming to visit dad? And they have a return ticket and a long history of visiting for holiday a returning to Mexico correctly?

I know this is a lot to take in, but it seems that there are many ways that the process can go wrong. We just want to make sure we are doing everything correctly.

Thank you very much for your time and help.