My understanding is that the DC's were changed because the scaling didn't make sense, and actually punished players for levelling up their ship. (I personally have no problem with the revised DC's, it seems to me most of the described actions should be routine excepting mishaps or extreme circumstances.) Presumably going back to the old DC's would reintroduce the scaling problem to your game, so it would depend on whether you're okay with that.
Agreed. With the base assumption in the rules seeming to indicate how wide spread starship use and access is, it doesn't make sense for starship anything to be as challenging as it was in the original math.
Hitting another starship in combat still averages out at about the same rate that hitting and missing in normal combat does which works well considering that shooting at a moving target while moving would be the most difficult part outside of piloting the ship itself. But an engineer or science officer to be so inherently unable to do their role makes absolutely no sense.
An actual pilot would be able to do most of those things if they were certified to fly so regularly failing at piloting checks also doesn't make sense.
I have found that most of the tension comes from an enemy doing damage to the player's ship, the same as normal combat. Tension because there are enemies sounds like a role playing problem and not a problem with the changed math for the mechanics. The math is easier for the enemy too so if the enemy is attempting to do what is most optimal, there should be plenty of damage trading and interesting encounters