I was thinking the other day and came up with a nifty idea.

[Suicide Junkie]

Hey, in P&N, you can stuff Null-space, Ion, Tachyon, and shield destroyer mines into the mine hulls.

You choose a size, and then mix and match from 1 to 3 warhead types. It keeps the number of objects down to a reasonable level.
(3 hulls + 3 normal warheads + 4 special warheads = 10 objects) rather than (3 * 7 * 3 = 63) basic mine hulls.

A lot less clutter too, since you only see the mines you feel are useful, and have a design for.