This is beyond my area, but: even in a vacuum of other developments, the "Age of Discovery" acted within a framework contextualized by ancient notions of colonization, especially Greek and Roman colonization (their post-antique world knew nothing of Phoenician overseas expansion at that point).

In the Greek colonial horizon, from the middle of the 8th century BCE onwards, the activity of colonization was strongly associated (variously) with notions of "getting a fresh start" for certain groups (a la the American colonies millennia later), with charismatic oikist (founder) figures (many of the early ones certainly apocryphal or quasi-legendary), and with opportunistic seizure of fresh markets, resources, et cetera. This is a concept that goes right back to Odyssey, probably approaching its final form in the 8th-7th century BCE. So in Book 9, Odysseus describes "goat island":

. . . but [the island], unsown and unplowed for all time, is deprived of men, and it feeds the bleating goats. For there are for the Cyclopes neither vermillion-cheeked ships, nor are there men skilled with ships among them, who could construct well-benched vessels which might accomplish each one’s wish, arriving at the cities of men, as often they cross the seas in ships to visit one another. [The Greeks] would make the island a well-built [settlement] for themselves. For the island indeed is in no way poor, but would bear all things in season. On it there are soft and well-watered meadows upon the shores of the grey sea. Grape-vines would be nearly immortal, there. And on it there is level plow land, where a deep harvest would heap up always, season after season, so rich is the soil beneath. At this place also is a harbor of good anchorage, so that there is no need of mooring-rope, nor to throw out anchor stones or to tie off the sterns of ships, but having beached the ship there is time to remain until the minds of the sailors should stir them on and the winds blow upon them. And upon the harbor’s headland a sparkling water flows, a spring from a grotto, and around it black poplars grow. (Od. 9.123-141)

Notice also that the odyssey narrator considers the inhabitants of "Goat Island," the Cyclopes, to be incapable of appreciating the land they inhabit or of exploiting its advantages. This leads to the notion of "civilizing" colonized territory, though this was not originally an impetus for the Greek colonial horizon. Retrospectively, though, the Greeks thought of their colonies as civilizing epicenters, especially in places like eastern Sicily and Massalia (Marseilles).

In the Roman sphere, colonization was much more focused on the extension of Roman state power, either through veteran soldier colonists or through "civilian" Roman citizens. Early on, Roman colonies were like forward operating bases or occupation garrisons. Augustus used the veteran colony as a nexus for seeding urbanization, especially in "under-developed" provinces like Gaul or the North African maghreb.

It's a blending of these two traditions which inform colonial aspirations in the Age of Discovery: resource acquisition, territorial control/garrison, and a secondary "civilizing" principle.