It's a long winded problem that comes back to PvE difficulty... In that there isn't any, not really. Cryptics idea of difficulty is to hike up the shield HP, hull HP and damage of NPCs to insane levels, rather then have them use damage/tanking skills. Heck most NPCs rarely have more then two skills, if that. As such, each space mission is basically all about DPS. Tanking is hilariously easy for all classes, so unless you're doing an STF you're not in much danger of dying. As said above, NPCs don't really use tanking skills (instead having allround high stats), so a sci captains debuff skills aren't much needed or much useful. The most useful thing a sci-ship can do is use crowd control abilities, like gravity well. It's only when you get into PvP that a sci-captain in a sci ship truly stands out. Escorts main defense is speed, which a sci ship can counter with tractor beam. Extend shields can be disabled with photonic shockwave. Buffs that are keeping a ship from being destroyed can be removed with subnucleonic beam. Team can get alot of extra tanking help from scattering field. STFs are like a halfway point between generic PvE and PvP, in that sci-ships do have more use in regards to crowd control, but DPS still reigns supreme.