Hello,
Can you control territory in ED and is there an active player base on PC to do this?
If so, which player factions are at war, who needs the help most?
Depends on what you mean by "control".
There's PowerPlay, there's the BGS and there's the Thargoid war.
Powerplay gets you some toys (like shields or guns), a few perks (like double bounty payouts) and some income (negligible until rank 4 of 5).
BGS gets you bragging rights like shown by
@nemolomen above, and possibly some influence at the unfolding of the overall ED storyline (which was the original motivation of
TTW three years+ ago)
The Thargoid war gets you the continued existence of mankind. Perhaps. Unless the
latest experiments of Azimuth will lead to our complete extinction.
As to who needs help most - that depends on which war you want to fight. There's a few thousand going on all the time.