Yeah I ran my business as a sole proprietorship for a long time, every time I talked to a tax accountant they said it just was better for how I was doing things. My wife's we incorporated almost right away.
So yeah talk to a good tax accountant about that.
Also talk to an insurance broker, we used to carry errors and omissions insurance for one business we had, and an activity where someone could drown I would want to at least know what my risk was and how much insurance would cost.
As for how it impacts EI there is a calculation I think, my dad mentioned it to me when I tried to pay him for work he was doing in our basement:
https://www.canada.ca/en/employment-...ile-claim.html
If you decide to do it all above board (i.e. track your income, keep some for taxes and report the income and pay your taxes) there's some good free online tools to do that. I used to use this one:
https://www.waveapps.com/
Very cool, easy to keep track of stuff, even generate invoices and generate reports for doing the taxes or sending to an accountant (you can even give them read-only access).