The training arena is very nice for practice, however, I think it has a very big limitation: While you can tell you've hit the target, you DON'T know the kid of damage you've done.
Would it be possible to have the TA set up so that even though lethality is turned down, it will report if fatal damage would have been inflicted?
I think this would be very useful for newer players, especially to teach them how while they may see hit sprites all over the target, most guns take concentrated fire to cause enough damage to knock off pieces. Additionally, experienced players who drop into the TA for sessions such as the wingman clinics, or squadrons doing aggressor training/etc may find it useful to know when they would have been killed. This would also be useful for practicing bombing and rocket attacks, where it can be hard to determine if your ordinance was on-target short of reviewing film afterwards.