Just jumping in to say - screw the F-104. The F-105 is the better choice! Thud all the way!
Seriously though, the untapped Cold War era aircraft are many and varied, and i'd buy all of them as soon as they're made available. Too much of DCS is MFD and glass cockpit systems work, i would love to see a return to stick and rudder, no FBW, early guided weapons, and get away from the overly modern birds (fun though they are).