What analytics tools do people like here?
One nice thing about it is that there are some pages on my site that I never bothered to add Google Analytics to, but Cloudflare adds their tracker automatically to every page. It couldn't be easier, which is great as analytics is not something I want to spend any time on.
... but if I wanted to run my own platform I wonder what other people are using.
What is wrong with PHP? Most hosting companies support it by default or come with LAMP images, so installation is often trivial.
I would pick a different stack today mostly due to wanting to try other stuff out, and not so much because something was broken about it. Website still loads faster than 99% of the internet today, and I'm happy with it.
Normally the analytics platform should be hosted on a separate server for performance and security reasons.
For example, the demo dashboard of uxwizz.com runs on PHP/MySQL on a $5/mo VPS and it's faster than most analytics platforms, even those running on big cloud infrastructures, because for the low-traffic use-case the simpler the solution and technology, the better.