Greetings
All factions can play on mobility card. Some just easier than others.
Ariadna is basically "get off my lawn" faction. The people are of little concern to the rest of the Human Sphere, however the planet Dawn they have settled has abundance of very rare and rich ore. Lately they've started to be more active on the political scene.
* Side note. Show your friend
Tank Hunter with Autocannon, to him it might be a selling model.
Haqqislam might be another example. The people separated from radical and conservative Islam on Earth and focused on more positive aspects. They have their darker side, since the planet they've settled has valuable substance called Silk. With it many marvellous medical things can be done, yet it also servers as a nice bargaining chip on the political and economical theatre.
Bakunin (Nomads) might also appeal to him. Very chaotic and prone to violance in the background, not so much as the underdog. More of an illegal space fearing black market.