Despite trying to be retired, it looks like I've got a contract to do some speed tuning. Trying to refresh my knowledge and came across this
https://whichloadsfaster.zomdir.com/#
Kind of cool, especially if you clone a site on a VPS and can make tunes to one version, then test against the original.
There are also some nice resources there
https://www.zomdir.com/wiki/en/knowledge-news-knowledge-internet-websites-performance/anywhere
And, for those of you who like throwbacks to the 90s, it's a good old directory site with a distinctly 90s styling