I agree. I work for a company who is a top 100 globally customer of Azure. In case where we have needed support, depending on how severe we define the issue, we are contacted within minutes. Well within the defined contact times stated as when creating support tickets. In several other cases, Microsoft has brought in people from around the world to help workout various issues. However, I don't know if the response times and help offered would be the the same if we were a different scale organization.

I'm just a private individual hosting his blog on Azure, and I've had a stellar experience. I made a post about some gripes I had setting up my website, and a person from the developer outreach program reached out to me and put me in touch with the engineering team directly. Turns out my main complaint (lack of support for managed SSL cert for root domains) was already in the pipeline. They even sent a bunch of MS/Azure gear to my doorstep as a thanks for my feedback.

Do you think you know or could guess an average response time for ticket responses?

We don't open enough tickets for this to be really meaningful (things generally work as expected), but I'd guess around 8h