I would say that these options might help you:
Thanks Antonio for quick reply. As advised, I am trying to figure out composite metrics, but is there a documentation somewhere I could refer to that could help me code the desired query with accepted syntax/metrics.
I wanted to have the representation where time consuming resource requests for a particular user action (like loading of PDP) could be seen. We can see it under waterfall Analysis but for business reporting purpose, wanted to have a kind of dashboard.
Have you checked the Data Explorer documentation pages? I include some for your reference:
I can't think of any way to get "requests" on a dashboard,. As you said, in DT currently in both cases, RUM and Synthetic, you would go to the waterfall or the page overview to find them.
Maybe something where @Jacek_Janowicz could help?
Other indirect alternatives
You can get a list of service requests from service metrics like (if you split by request):