Honestly, I've always found CRA friendly, competent, and responsive.
But, I also don't run a small business, and am just a tax payer. Though when I had a small consultancy and corporation they were also actually fine to deal with.
Do you have kids? If so, did you try to deduct extracurricular activities? I did and was audited, also 100% of my friends were audited for the kids related deductions.
Anecdata of course.
Also I find Canadian personal taxes are way too complicated. I can think only of Italy where allegedly personal taxes even more complex.
I used to do those deductions for my kids, yep. Never had a problem.
I seem to recall from the last 4 or 5 filings that those deductions are gone now. The only thing I had to do each year was figure out the capital gains on my RSUs (in USD, so a bit fiddly). And now this year I have nothing like that, so it's just "here's my RRSP contributions, and yes, those T4s look like mine, confirmed, ok bye"
You're throwing around the word "audit" far too casually. In all likeliness, you and your friends were not audited. The CRA probably asked you to submit supporting documents such as receipts and other written records to prove your claim, as you are legally required to do.
But, I also don't run a small business, and am just a tax payer. Though when I had a small consultancy and corporation they were also actually fine to deal with.