Pervasive Economy is a godsend, pretty much giving you a resource advantage by default.  Insurgency varies a bit.  If your opponent puts hanger defenses in all his planets (I do late game) it's virtually worthless since the actual size of the raids are so small that a few strike craft can deal with them before they actually damage something.  Worse, if an enemy capital ship is present, it's free experience for them.

u get a percentage of the money spent. Obviously the higher the fleet upkeep the less money spent by the enemy, but even at full fleet upkeep that's 47% income lost, and that amount of ships isnt needed unless you're playing a HUGE map.

As I said, one hanger bay will deal with insurgency quite easily. Since it's not necessarily a bad idea to put a hanger bay in each of your planets late game (especially against TEC with timed explosives.  A couple scouts with timed explosives running around behind enemy lines are a lot more annoying and dangerous than insurgency), you can't exactly just say you've incurred a direct cost on your enemy.  It doesn't help insurgency's case that it gives enemy caps free experience over time.

Unfortunately, insurgency is something of an AI exploit, since they will sometimes send their entire fleet to deal with a couple rebels that attacked an undefended asteroid.  This leaves their front lines completely defenseless to my main fleet.  However, by this point in the game the AI is usually several tech levels behind you anyways so you should be walking all over them.  Against a player, I can't see playing on a map which this would be worthwhile.  If he's not turtling, I'd be inclined to use scout frigates to harass, not insurgency, and if he is turtling then insurgency will only help him get valuable exp.  As I said, I don't think this one is worth your time or effort.