In space PvE, Acc is. . .less important. Defense values of NPCs are pretty low, so they're easy to hit. Best mods to use are Dmg, CritH/D.
In Space PvP (where your stats are actually put to the test), Acc is crucial. You can't DPS if 2/3 of your shots miss the target due to high defense values (which happens a lot with escorts, especially if they're running Omega or evasive maneuvers). So, you can go with a [Acc]x2 [CrtH/D] setup, or run [Acc]x3 (which is expensive, EC-wise).