One of the most interesting archeological finds in Greece over the past decade has been the Kasta Tumulus and tomb at Amphipolis, Macedonia. Inside (and at the ceiling) of this Hellenistic c. 320 BC tomb (and on stones used for the tomb's exterior ashlar wall) signature marks of Alexander III's deputy commander Hephaestion were found (according to the architect and the tomb's excavators). I have written about it in a series of papers I have authored on Kasta that you can find on this site under my name.
The best known hero of Greece and the Mediterranean is Hercules, with probably no historic links, but the hero type legendised and mythologised into the landscape. Perhaps your examination of inscribed monuments could start with the various Pillars of Hercules, and the universal impulse to make landmarks. I have published a magazine edition on the archetypal features attributed to Hercules in the Peloponnese, Greece, and eastern Mediterranean. Here are two links to two extracts from that publication: https://stoneprintjournal.wordpress.com/2021/01/16/hercules-arcadia-and-greece-myth-maps/
and on https://mindprintart.wordpress.com/2021/01/16/an-italian-mural-of-hercules-in-greek-arcadia/