I have three suggestions:
Increase collision damage;
Make stealth an option in FRED2;
Make an option to select a different support ship for a mission;
Make a sexp to cause the selected ship to make a kamikaze run for the target ship.
Increasing collision damage will make everything seem more realistic. It'll also make you fly more carefully, especially around capital ships, like you should.
It would be cool to be able to select a ship as a stealth ship in FRED2. This way we can do away with the red blip that keeps its presense when a ship is not visible to sensors. You could also switch on and off your stealth, which could have its own novalties for mission designers.
This is low priority, but it would be good if we could select a different support ship in a mission. It would work great for the FSPort group, so that you could still summon the old Centaur if selected in each mission, while the default could still be the Hygeia.
"Prepare for ramming speed!" Says Worf. Now wouldn't a Vasudan feel the same way? His ship is on fire, almost destroyed, almost dead. But he sets a collision course to the enemy ship to take out the enemy with him. I know you can do Kamikaze in FS2, but what if the ship wants to fight first, and when it gets to a certain hull damage, you could select a Sexp to make it go Kamikaze with the particular target.
There was another suggestion I had, but I forget

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