I'm definitely voting for Qirex! Nothing beats the twin-hulled purple brick.

Icaras would be good, too.

And I wouldn't even bother modelling the atrocious "cokestyle" ships if I were you. Want to know what it looked like? Grab a bottle of Coke, that's what it looked like. No, not even with wings added on or anything. 8 P

The "classic 4" are FEISAR, AG-Systems, Auricom, and Qirex. So those would be a great set to make. Pirhana is also the "standard" 5th ship. Goteki, Assegai, and Icaras are the 6th, 7th, and 8th respectively.

So so far you're making them in the order they were originally made! 8 )