I think class balance is a real issue and I think there are some viable ideas here. I dont understand people thinking sci is overpowered, i guess their own experiences have led them to that conclusion. My expereience has forced my sci captains into escorts and that does seem to work at killing things.
Tactical Officers shouldn't be buffing damage that isn't attributed to weapons systems. I think we can all agree on that. For Science, Sensor Scan's effect should scale with the Starship Sensors skill and increase proportionally to the number of Sensor Analysis stacks you have on your target. Engineers... I'm not so sure. Ideas?