I'm no expert on game networking, but the assumption that 3 updates per second for a twich game seems low. For strategy games, fine, even perhaps excessive. If you do a google you can find a really cool article about some of the tricks they used in the old days to get age of empires to work well over modem connections with so many units, including things like predictive movement, which can still be used today. But even so, we make a hell of a lot more than 3 adjustments per second when flying out ships in the middle of combat (including firing weapons, chaff, etc). The lower the value, the less "fidelity" you get.
Maybe 3 times per second is enough. No idea what ED uses for its P2P instances.