DLC 1(Blood and titanium) interact with the geoscape and the other human factions that inhabit the earth, but there is a distinct lack of of this in DLC 2(Legacy of the ancients). (Big tangent with huge reworks incoming)

Pandorans evolve insanely quick. One would think that the materials gathered in Antediluvian sites could easily aid the pandorans as well as humans(Might not be canonically correct but hear me out). The non-existent time pressure regarding securing these materials for humanity is because the pandorans are completely unaware of these sites before PP clears them out(No negative feedback from not exploring DLC).

Now if another version of the game would allow the pandorans to engage the ancients some time after achieving sufficient military strength(Scylla+), they would be able to evolve incredibly strong mutations with the help of these materials. These mutations would be exclusive to fights in "close" proximity to the conquered resource site.

This could, in turn, affect the late game by having the pandorans focusing their efforts on sites located close to the Pandoran Palace so that these buffed evolutions are present if the player chooses to not address the issue, resulting in a more complicated last mission.

Another possible feature would be that the pandorans prioritize securing strategic resources to strengthen itself, instead of attacking havens.

This change would increase enemy variation, create geographically important areas to consider, and possibly mix things up in the late game.