It was amusing that he used that compass line of sorts to demo just how the distance compared with Greenland etc. :^) The tax collection on imported goods from India (plus the stuff that Roman-era traders sold there) fattened the coffers and went a long way in building and maintaining the Empire as a whole. There’s a document that survived that is one ship’s manifest apparently compiled by the tax assessor, and the largest part of the cargo from India (but not the only part) consisted of over 600 tons of pepper.
By contrast, a good many of the provinces didn’t generate enough tax to support the garrisoning of the province itself. Caledonia was so poor and underpopulated (kinda like now, except we call it Scotland) that the Romans never bothered to add it to the Empire. OTOH, for some period of time Copenhagen was apparently under Roman rule, which makes sense as it controls trade in and out of the Baltic. Iron processing came into its own along the Baltic shores during the Roman Empire.
Likewise Hibernia (Ireland) was not added, although a trading post was apparently built on a promontory (Drumanagh) not far north of modern Dublin, and Agricola was given an extension in his term as governor of Britain, and built a long-lived fortress at modern Chester, possibly with a view of moving the capital there after finishing up in Ireland and Scotland.
I know they found a Roman statue on an ancient ship wreck somewhere off the coast of...Brazil? And then there is the reputed discovery of an Olmec head that had Caucasoid features (sharp nose, prominent brow and chin) that was later destroyed via “target practice” the same way The Sphinx’s face was mutilated. Maybe one day there will be evidence discovered of a Roman settlement in the Americas.